NextGen Results

NextGen VOICES: Results

We asked young scientists to answer this question:

You can travel back in time to share one piece of scientific knowledge from today. Where do you go? Describe the date and place you choose, the information you share, and how it might change the course of history. (Assume that the people you visit will understand and believe you!)

In the 5 July 2013 issue, we ran excerpts from 13 of the many interesting responses we received. Below, you will find the full versions of those 13 essays (in the order they were printed) as well as the best of the other submissions we received (ordered chronologically by the historical period each chose to visit).

Would you like to participate in the next NextGen VOICES survey? To make your voice heard, go to http://scim.ag/NextGen_8.

(Can't get enough NextGen? See the results of previous surveys at http://scim.ag/NextGenResults, http://scim.ag/NextGen2Results, http://scim.ag/NextGen3Results, http://scim.ag/NextGen4Results, http://scim.ag/NextGen5Results, and http://scim.ag/NextGen6_Results.)

Essays in print

440 B.C.E.: What is Life? 800 C.E.: What is Life? 1450 C.E.: What is Life? 2013 C.E.: What is Life? This fundamental question has been on the minds of philosophers and scientists since the beginning of time, yet even now we do not have a widely accepted answer. The line between what is biotic and what is abiotic becomes blurred as soon as we start focusing on the molecular principles of what we call living systems. But by observing and studying these molecular mechanisms we are a few steps closer to answering this longstanding question. That's why I would travel back to the year around 600 to 400 B.C.E., when there were heated debates in ancient Greece about the origin of life. I would tell the philosophers and lecturers of that time what we now know about life on a molecular level, showing them that life is not a miracle, but that it can be explained and studied. I would like to see the impact this would have on art, industry, science, and religion throughout the centuries to come. This might even accelerate the onset of the scientific and industrial era by reducing the impact of religion in everyday life and perhaps even allow different cultures to understand each other better, once they realize that our nature is essentially the same.
Martin Pačesa
National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, 62500, Czech Republic.
E-mail: martin.pacesa{at}kxdesign.com

In 212 B.C.E., a Roman soldier inadvertently killed Archimedes, the father of Pi and of his eponymous hydrostatic principle. As evidenced by the Archimedes Palimpsest, a long-lost manuscript that details the first explicit use of infinitesimals, he was on the verge of discovering calculus, which in its modern form was not formally introduced to the world until the 17th century by Newton and Leibnitz. If I could travel back in time, I would transport to Syracuse, Sicily during 222 B.C.E. to introduce the fundamental theorem of calculus to Archimedes 10 years before his death. As the great mathematical genius of his era, he would have been most poised to understand and disseminate the knowledge of linking the concept of a derivate of a function with the concept of the integral. An earlier introduction of calculus, which is used in nearly every branch of science, would accelerate discovery of the natural world by allowing the modeling of systems that change. So much technology of today, from the internal combustion engine, to the principles of economics, has been made possible due to calculus. Perhaps in the present era we would be traveling in flying cars, or we would have colonized Mars. Or, more grimly, we would have achieved nuclear apocalypse. Undoubtedly, however, had calculus been introduced to the world 1900 years earlier than it was, the impact on humankind would be immeasurably large.
Jugal K. Shah
School of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA.
E-mail:jugal.shah{at}ucsf.edu

221 B.C.E., Xianyang, China. The majestic Emperor Qin, who has conquered all opposing states and unified China, is declaring to the whole world that the great and the first feudal dynasty has been established. Fortunately, I travel back in time just to be here and see the unrivalled state celebration. As the future scientific envoy, I have an audience with Emperor Qin and present my gift: women are capable of doing the same thing as men; they even can do better. Certainly, with adequate data, glorious accomplishment stories, and plenty of examples, such as Madame Curie, Mrs. Thatcher, Deng Yaping, and Oprah Winfrey, I can convince Emperor Qin to abandon the wifely submission and virtue concept stemming from the stern Confucianism System and give women more chances to receive education and give full play to their talent in science and technology, culture, politics, and the military. In that way, more than 2000 years later, China would surely be a super power stronger than today, and the Chinese nation would never have suffered dishonor during the late Qing dynasty when we were derisively called the "sick man of East Asia" and at the mercy of other countries.
Jian Zhang
School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou, Guangdong, 510641, China.
E-mail: zhangjian3954{at}126.com

I would go back to ancient Rome on the morning of 15 March, 44 B.C.E., to the steps of the Roman Senate, and share Bayes' Theorem with Julius Caesar. In the days leading up to his assassination, Rome was awash with rumors of an assassination plot. According to legend, an old soothsayer had forewarned Caesar himself of a great danger that threatened him on the Ides of March, and Caesar's own wife Calpurnia had a premonition of her husband's murder and tried to warn him of the danger. But were these dark forebodings and dire prophecies just idle gossip (noise) or a credible forecast of the future (signal)? Given this uncertainty, I would have advised Caesar to guess the prior probability of an assassination plot and then update his prior based on the sundry rumors swirling around Rome. Had Caesar applied Bayesian reasoning, it is likely he would have followed his wife's advice and stayed home on that fateful day. Had he done so, Bayes' Rule might have changed the course of history, for the Roman Republic might have yet been saved, and perhaps we would all still be speaking Latin.
Enrique Guerra-Pujol
Dwayne O. Andreas School of Law, Barry University, Orlando, FL 32807, USA.
E-mail: eguerra{at}barry.edu

I would travel to China in the year 1070 with the knowledge of bacteria and fungi that produce substances capable of fighting infection. In 1070, Su Song compiled the Bencao Tujing, a revolutionary treatise on pharmaceutical botany, zoology, and mineralogy. By providing Su Song this knowledge, it would be in the hands of an individual capable of understanding, utilizing, and preserving this knowledge. Su's treatise survived until the 16th century, when it was incorporated into the Bencao Gangmu by Li Shizhen, demonstrating the lasting impact of his work. After Su demonstrated the efficacy of fungi, such as penicillium, during the Song Dynasty, which oversaw some of the most significant scientific advances in Chinese history, antibiotic pharmaceutical preparations would likely be developed. It would be over 250 years before arguably the most devastating pandemic in recorded history, the Black Death (caused by Yersinia Pestis), would arise in China, spreading west as far as Europe. The Black Death was responsible for over 100 million deaths, a significant part of the known world population at the time. In addition to the tragic death toll it exerted, the Black Death led to massive social unrest, including economic decline and widespread persecution of those thought responsible. Providing Su Song with antibiotic knowledge in 1070 would allow ample time for development of appropriate therapies to combat the Black Death at its source, averting one of the greatest tragedies in the history of mankind.
Zeshaan N. Maan
Department of Surgery, Stanford University, Stanford, CA 94305, USA.
E-mail: zmaan{at}stanford.edu

In 1687, Sir Isaac Newton published his Principia outlining the fundamentals of what quickly became called Newtonian mechanics. I would travel back to Cambridge England 5 years prior to this date and teach Einstein's theory of relativity to Isaac Newton. The obvious change in history resulting from this action would of course be a massive head start for the field of modern physics. Much of what has happened in the discipline of physics since Einstein, such as quantum mechanics, atomic physics, and the detection of black holes, may have happened much earlier in history, and who knows where physics would be today. However, I would argue that a less obvious but possibly more important consequence of this historical change would be its effect on how we teach science. Currently high school students and first-year undergraduates are taught the limited version of physics discovered by Newton. Only students who choose to continue in the discipline learn Einstein's more generalized form of mechanics and how classical mechanics is encompassed in this modern understanding. If Newton had discovered both his and Einstein's contributions at the same time, the result would be an educational system that introduces a more complete view of physics to a wider audience of people from an earlier age. Given that our current educational system propagates the knowledge of a sole 17th century physicist, improving the knowledge of that physicist may be the only way to bring our education system into the 21st century.
Matthew Hammond
Department of Biochemistry, University of Pennsylvania, Philadelphia, PA 19104, USA.
E-mail: mhamm{at}sas.upenn.edu

Scientific information is typically useful because of the vast amount of supporting knowledge, theory, and technology already in place. Instead of a piece of technical knowledge, I would share something that would provide perspective: the photo of Earth taken by the Apollo 17 astronauts in 1972. "The Blue Marble," as it is often called, shows both the unity and finitude of the planet and its resources. The photo is emblematic of the modern environmental movement's birth in the 1970s. I would bring this photo to early 19th-century Britain, during the Industrial Revolution, when consumption of Earth's resources began to increase dramatically. Providing this information 150 years earlier would be an opportunity for the soon-to-be industrialized culture of western Europe to reconsider its relationship with the planet. Granted, we are quite poor at maintaining a "Blue Marble" perspective even in the 21st century, but a 150-year head start might put the planet in a less precarious situation today. For a little extra perspective, I would share the photo with its original orientation, Southern Hemisphere on top!
Steven M. Roels
Department of Zoology, Michigan State University, East Lansing, MI 48824, USA.
E-mail: roelsste{at}msu.edu

I would travel back to 1847 to join Hungarian physician Ignaz Semmelweis at the Vienna General Hospital in his hand-washing crusade. At that time Puerperal fever was epidemic, but its etiology unknown. After observing mortality from the disease to be three-fold higher in doctors wards compared to the wards run by midwifes, Semmelweis drew up his novel intervention: hand-washing by physicians using a chlorinated lime solution. However, the medical fraternity vehemently rejected his proposed intervention, and ostracized him for it; effectively hanging him like a witch on the outskirts of town for going against the conventional wisdom. In hindsight, while we marvel at the brilliance and simplicity of Semmelweis's work, we have done little to celebrate a practice of accepting simple and unconventional work, even when backed by solid thorough science. Traveling back to the time of Semmelweis, I would share the importance of embracing such unconventional work when supported by sound evidence and stringent scientific process. The modern scientific communities approach has been byzantine in this regard. It is as if the witch remains hoisted up on the outskirts, with modern scientists reluctant and indeed disincentivized to accept alternative findings. Laying the foundation with Semmelweis, one can hope to cultivate a scientific culture founded in discussion and driven by radical innovation; encouraging the willingness and openness needed to accept alternative ideas—even those that may conflict with one's own beliefs. After all, this is the promised vision of the scientific community, but it has yet to come into fruition.
Samuel D. Rutledge
Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24060, USA.
E-mail: srut07{at}vt.edu

The implementation of modern day knowledge depends heavily on specific industrial developments. How can knowledge effect a change in the course of history in the absence of those developments? (i) Direct feedback about the unforeseen effects of the implementation of a particular piece of scientific knowledge at that particular time in history might prompt the scientists and inventors of that time to search for alternatives. If I could travel back in time, I would travel to the Dayton Research Laboratories in the year 1920. There I would explain to Thomas Midgley, Jr. and Charles Kettering the long-term negative effects of leaded gasoline and chlorofluorocarbons. Understanding of these long-term irreversible effects in the early 1900s would prevent the respective lead poisoning and ozone depletion that still troubles the world today. (ii) Nowadays it is easy to forget that communication among scientists once was difficult, due to geographic and linguistic boundaries. A striking example is that of Charles Darwin and Gregor Mendel. Their written legacy allowed for the advance in genetics, yet they never met in life. If I could travel back in time I would go to Downe, England in 1866 and inform Charles Darwin of Gregor Mendel's results. Realizing that Mendel's work provided the proof for evolution by natural selection this would result in a Modern Synthesis 50 years ahead of time and advance medical genetics with 50 years. Accordingly we would be much further in our understanding of human genetic diseases and closer to their treatments.
Antoine de Morrée
Paul F. Glenn Laboratories for the Biology of Aging and Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA.
E-mail: demorree{at}stanford.edu

I met Alfred Nobel in Sweden in 1895, a few days before he died. I told him I came from the future and, amazingly, he believed me. He had just finished writing his last will, leaving much of his wealth to honor outstanding achievements in physics, chemistry, medicine, literature, and peace. He was probably unaware of how his testament would influence mankind. While drinking coffee together, he asked me if I wanted to share a piece of scientific knowledge from 2013. I told him that in the future scientists are communicators, writers needing to share ideas with clarity to different audiences. I described the new and diverse ways of communicating science in the time to come. He smiled, enjoying looking into the future through my eyes. We both agreed that better science communicators are, ultimately, better scientists and that science is not just for scientists. When he fell asleep, I returned to the future. Though he thought my visit was part of his nap's dreams, minutes before dying he included an award for science communication in the Nobel list. Ever since, writing and communication have become part of the syllabus in undergraduate and graduate programs, together with physics and chemistry. More efficient scientific communication has accelerated the pace of discoveries, created greater public scientific awareness, literacy, and crowd-funding, and inspired young generations to pursue careers in science. More than 108 academics have already been honored with the Nobel Prize in Science Communication. I hope one day I will win this award!
Paula de Tezanos Pinto
IEGEBA, Laboratorio de Limnología, Departamento de Ecología, Genética y Evolución, Universidad de Buenos Aires, C1428EHA, Buenos Aires, Argentina.
E-mail: paulatezanos{at}ege.fcen.uba.ar

It was a winter night in 1896. Two Swedish scientists, Svante Arrhenius and Arvid Högbom, were chatting in Arrhenius's office room. "I believe a doubling of atmospheric CO2 would give a total warming of 5°C to 6°C," said Arrhenius. Högbom agreed, but they both thought the warming would take thousands of years. At this point, I decided to show up. Rather than falling from the chimney like Santa Claus, I chose to knock on their door. They were really shocked when they found a Chinese girl standing in front of them. "Hello, Professors, I travel back in time from 2013 to tell you that global warming starts now. Since the early 20th century, Earth's mean surface temperature has increased by about 0.8°C. The primary cause is greenhouse gases produced by human activities. The Intergovernmental Panel on Climate Change indicated that during the 21st century the global surface temperature is likely to rise another 1.1°C to 2.9°C, even for their lowest emissions scenario. Global warming isn't just about things getting hotter; other changes include stormier, drier, and even colder conditions." The next day, they wrote to the government and the scientific associations to call people's attention to global warming and adaptations to eliminate it. Actions like reducing fossil fuel use, planting trees, and conserving water were known by people all over the world. Instead of destroying the planet, every single man on Earth began to protect and sustain it in their daily life.
Qifei Han
State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, Xinjiang 830011, China.
E-mail: hanqifei08{at}mails.ucas.ac.cn
Acknowledgments: The author thanks her supervisors, Xi Chen and Geping Luo for their useful advice. This essay is funded by the National Basic Research Program of China (2009CB825105).

I would choose Thomas Edison in the beginning of the year 1900 in New York City. I would describe the events of the future and how he and I could help keep our environment cleaner. I would give him designs to solar panels and hope that the future of solar technology would make America and other countries independent of oil production. Thomas Edison's name alone could create Edison Panels that would be on every Victorian home in the world, especially in hard-to-reach locations in the world. Fewer trees would be cut and the world would remain more rural and yet prosper from a new power source.
Dan Ferrell
Alexandria, VA 22305, USA.
E-mail: dannielferrell{at}yahoo.com

It's 24 July 1948, and I'm at the Palais des Nations, Geneva, Switzerland. I walk into the resting room of Dr. George Brock Chisholm, who is about to be appointed the first Director-General of the World Health Organization. I tell him that I come from the 21st century, and that people in my time are suffering from the increasing prevalence of antimicrobial-resistant bacterial infections, mainly as a result of the misuse of antibiotics. I urge him, in a time penicillin is just being mass-produced, to emphasize the importance of appropriate antibiotic use to the world, and to develop and promote policies of proper use of antibiotics. He believes in me, and delivers the message in his acceptance speech. During his 5 years in office, he is actively involved in the development and promotion of national medicines policies and guidelines on proper antibiotic use. These include delivery of antibiotics only under prescription and accurate and clear instructions to patients needing antimicrobial treatments. With these important guidelines introduced and promoted much earlier, the threat of global antimicrobial resistance is much minimized when I come back to the present, although we all know that the battle against antimicrobial resistance is far from over.
Man Kit Cheung
School of Life Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China.
E-mail: mkcheung{at}cuhk.edu.hk

Top Online Essays

I would share the physical arrangement of the Sun, Earth, other planets in our solar system, and their satellites, and an understanding of the distances to stars and their composition (more or less the same as our own, some bigger, some smaller). I would share this with people at the dawn of sedentary farming practices. The impacts of this information would be twofold: First, it would inform farming practices and allow more rapid development of cultures. Second, and more important, it would unify the concept of the Universe that various cultures have and might dull the intensity of religious beliefs, or at least reduce the conflicts between them. This reduction of religious disagreement would in turn reduce the level of political conflict and allow more trade between cultures, greater retention of knowledge though time, and greater transference of knowledge between cultures. All of these effects would advance the state of our science and unify the world's cultures, putting us further along the path towards peace and prosperity.
Aaron Michael King
Davis, CA 95616, USA.
E-mail: amking{at}ucdavis.edu

I would go back to the ancient era when true written language was developed (likely ~3200 B.C.E. around Mesopotamia) and I would bring with me the designs for a printing press. I would impress upon the people and scholars of that era to record, copy, and share all of their knowledge. I would promote the scientific method to evaluate ideas, but I would maintain all knowledge should be kept; even if they believe it is wrong, it may have merit later. The written word has allowed us to accumulate knowledge faster than we can lose it. And it is through the cheap reproduction and sharing of that knowledge with the help of the printing press that we educate the world, reevaluate our ideas, and cultivate new ones. Our science, technology, law, culture, morality, ethics, and everything else that makes us human advanced immeasurably in every generation during which we could build on those ideas from the generation before. I do not need to bring back any specific scientific idea; if science really is an objectively constructed model of reality, then they will rediscover all that we have when given enough time. But with the ability to record and share those ideas, I believe their progress would be exponential. I cannot comprehend let alone conceive of how advanced we would be if the Dark Ages were erased and the Age of Reason began thousands of years earlier. But I believe we would be closer to the better people we want to be.
Neilson Nguyen
Department of Chemistry, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada.
E-mail: neilson.nguyen{at}utoronto.ca

Three other items made my short list—germ theory, Mendelian genetics, and iron metallurgy—but my personal favorite is a simple globe. It is easily understood, easily copied and shared, extremely useful, and if carried back to early Middle Eastern ancient empires like that of the Sumerians (approximately 3000–2500 B.C.E.), would quickly spread to the establishing dynasty in Egypt and soon-to-be dynasty in China, and from there throughout the world and history. Humanity's view of the world and the heavens would never be the same.
Chad Brick
Promerus LLC, Brecksville, OH 44141, USA.
E-mail: chad_brick{at}sumibe.co.jp

I would travel approximately 3000 years back in time and into the Middle East. There I would meet Abraham, the alleged founder of monotheism, and share with him Darwin's theory of biological evolution. This could influence him and his successors (Moses, Jesus/Paul, Mohammed) to focus more on tolerance instead on exclusion of unbelievers when creating their religion. So there would be a chance of making history less violent, increasing human interaction across boundaries, and accelerating development. Furthermore, assuming that Abraham et al. really had contact with god, their knowledge of evolution would enrich their holy books with interesting conversations.
Felix Stock
Munich, Bavaria, 80809, Germany.
E-mail:fx.sk{at}web.de

I'd like to travel back to ancient China when the school began to come into its own. One piece of current scientific knowledge I hope to share with the old Chinese is "open education." In ancient China, the idea that youngsters must amenably follow the teacher had been the prisoner of thought for a long time. The students in school seldom competed against the seniors, which became a hurdle to achieving excellence and creativity. Education is not just passing on knowledge but also a set of approaches to encourage scientific discovery. The understanding and practice of open education could help Chinese students to foster independent and innovative thinking, and best prepare teachers to detect their interests and talent. More essential, the mode of open education could greatly enlighten the old educators and youngsters who are supposed to uncover new knowledge collectively. I believe that a pioneer spread of open education would add diversity to the landscape and bring a whole new dimension to the development of education in China.
Jiang Zhao
School of Automation Science and Electrical Engineering, Beihang University, Beijing, Beijing, 100191, China.
E-mail: jzhao{at}asee.buaa.edu.cn

The Higgs boson has been found! Its existence, now confirmed, helps solve one of the most fundamental mysteries of all times: the origins of mass. My science time travel would have Mount Sinai as destination, in order to meet Moses as he descended with the Ten Commandments. First, I would share the profound scientific explanation of why stuff is made of matter. We would revisit the genesis creation narrative. Moses, a one-man army receiving laws directly from God, might be positively surprised to realize how scientists can extract knowledge from nature. Next, I would stress that such an intellectual achievement parallels a technological one: the largest machine ever built, the most precise measurements ever made, and the possibility to observe the smallest confines of the universe at unimaginable scales. Perhaps that would temper his wrath on people adoring golden idols. Crashing tablets would give way to hadron collisions. Last, I would substantiate that the discovery of the Higgs represents a collective achievement transcending nations, religions, and politics; a paradigm of collaboration, effort, and humility. Planting the seed of confidence in the potential of human beings back in the dawn of the ages is, no doubt, a monumental investment. Were these ideals to be held by one of the most respected prophets of three major religious traditions such as Judaism, Christianity, and Islam, the evolution of the human mind would be expedited. It might only take education and a tiny boson to place us at the edge of the Unknown.
Alex Gomez-Marin
Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, Lisbon, 1400-038, Portugal.
E-mail: agomezmarin{at}gmail.com

I'd teach Moses about the germ theory of disease. Demonstrations (such as boiling water and cleanliness during childbirth or minor surgery) should be convincing. I wouldn't couch the consequences as religious law, but perhaps the tests could be: the ritual of the boiling water. This would ensure the information is preserved in written form and communicated over the centuries, and hopefully would also encourage scientific testing in biology to make other discoveries. It might also reduce anti-Semitism in Europe, since then the Jews would be the authority on medicine. It would save untold millions from death by disease.
Ryan Lackey
CryptoSeal, Inc., San Francisco, CA 94104–5401, USA.
E-mail: ryan{at}cryptoseal.com

I would choose the printing press. Not exactly technology of today, per se, however it is relatively recent in comparison. I would take the printing press to ancient Egypt circa 1285 B.C.E. This would be during the reign of Ramses the Great and a time when Egypt was prospering. The printing press arguably was one of the main causes of the Industrial Revolution. With the relatively easy dissemination of information, people were more likely to learn to read and to apply what they read. If it had been invented at the time of Ramses II, I believe that people would have started to embrace reading and it may very well have begun a time when more than just a small subset of people (the scribes) were educated. In turn that may have changed the course of human history. By starting wide-spread education, the Industrial Revolution may have begun almost 2000 years ago. The ideas of democracy put forth by the Romans may have spread across the world. People may have ventured into space by the time of Christ. By this time, we may very well have colonized the solar system and ventured much further into space. It may even mean we had found other life forms not from Earth. Diseases may no longer be an issue for the human race and our life spans may span centuries rather than being confined to just one.
Christina Lynn Rush
Department of Life Sciences, Salish Kootenai College, Pablo, MT 59855, USA.
E-mail: christina_rush{at}skc.edu

If you accept the invention of modern printing as a "piece of scientific knowledge" I would definitely try to show the ancient Greeks how information can be spread faster and to a bigger audience than by hand-writing or word of mouth. The relatively simple design would allow rebuilding the equipment with available technology and operating without additional advanced technology like electricity. I think it is quite easy to imagine the tremendous impact on the development of a society if not only an elite minority had access to all kinds of information, news, and literature more than 2000 years before Gutenberg's invention.
Hüseyin Besir
Heidelberg, 69117, Germany.
E-mail: besir{at}embl.de

If I could travel back in time I'd definitely teletransport myself in ancient Middle East, precisely in the town of Gibeon during or maybe a little bit before the legendary war between the king of Jerusalem and Joshua, chief of Israel. This war is described in the Bible. Then I'd try to meet Joshua and I'd explain to him the heliocentric theory and Kepler's laws, taking with me from home a good telescope. In fact, during the battle, Joshua, believing in geocentric theory as everybody in those days, said "Sun, stand still over Gibeon, and you, moon, over the Valley of Aijalon!" to ensure himself the victory, and God granted his wish. In the case that he trusted me and understood that the Sun is fixed in the center of the Solar System he would never have uttered this fateful phrase, used over the centuries from the Catholic Church to discredit the scientists and the discovery of the heliocentric theory. Maybe Galileo and many others wouldn't have been punished, and the story, particularly for scientists, would definitely have been different and better.
Giuseppe Ferrillo
University of Naples Federico II, Casal di Principe, Caserta, 81033, Italy.
E-mail: giosepherrillo{at}gmail.com

I would travel to Bodh Gaya (India) 2500 years ago, and hope to encounter Siddhartha Gautama Buddha immediately after he became enlightened. In this auspicious window of understanding, I would express to him the central tenets of quantum mechanics and relativity, focusing on the idea of the observer effect, the importance of frame-of-reference, the dimensionality of reality, and most important, the non-duality of matter and energy. To give the Buddha a deep look into the nature of modern physics would complement his newfound wisdom on the essential attributes of the inner landscape of the human mind and soul. Equipped with these two modes of wisdom, his teachings could intertwine the two together like helical dsDNA, creating a novel philosophy that would speak to the both the evolutionary mind and higher spirit, which currently wage warfare within the psyche of modern man. Such a balanced path from the past would lead cleanly into a modern society that values the common origin of matter and mind: two twins, parted at creation, who thirst for the return to a singularity.
Daniel Ari Friedman
Department of Evolution and Ecology, University of California, Davis, Davis, CA 95616, USA.
E-mail: danielarifriedman{at}gmail.com

I would choose ancient Greece (350 B.C.E.) and share with Aristotle the existence of a microscopic world, because he was a very influential thinker and this subject implies very fundamental and practical issues of which every person should be aware. The impact of this communication could radically change the way humanity saw the world. Historical problems about epidemic events (the plague), crops pests (with the migrations implied), cattle illness, human diseases, and food storage could be explained not in a mystical but a rational way and practical solutions could be found. I think a lot of human suffering could be avoided with this information and healthier societies could be built, including more spiritual not political religions.
Jerónimo Ramírez
UNAM, Mexico City, D.F., 6470, Mexico.
E-mail: herominos{at}gmail.com

I would go to ancient Greece in 340 B.C.E. and present Aristotle and his student, Alexander III of Macedon, with an accurate map of the world. That information would probably be both relevant for Alexander's needs and actionable by him. The map might cause him to adjust his campaign strategy and goals to better match the true size of the world and perhaps prolong his life. The historical outcome could be unpredictable but interesting, at least as a test of the importance of individuals to history. Who knows, it might even influence the development of some major religions.
Esko Rantala
Kauniainen, FIN-02700, Finland.
E-mail: eskon_viesti{at}hotmail.com

I would take the knowledge of the scientific method and that all observed phenomena are the consequence of natural laws to ancient Greece, circa 300 B.C.E. Although this isn't a particular piece of scientific knowledge, I believe it would nucleate the most prolific effect that any knowledge at any time could have. At the time, the ideas of Pythagoras, Plato, and Aristotle reigned supreme—that there was a higher order to the universe, and that some divine symmetries must exist; that everything has purpose and that natural knowledge could be obtained by means other than rigorous scientific testing. Democritus, as the second human to believe in the existence of the atom, was of a different and more "scientific" opinion that that of the Pythagoreans, but unfortunately his views proved the loser among the Hellenic intelligentsia. It would be another millennium before the Arab scholars reintroduced the scientific method to spectacular results. Had the ideas of Democritus prevailed in the 5th and 4th centuries B.C.E., I strongly believe the human race would be a thousand years more advanced, and that much closer to joining a cosmopolitan community.
Djem Ulian Kissiov
Department of Genetics, Cambridge University, The Wellcome Trust/Cancer Research UK Gurdon Institute, Cambridge, Cambridgeshire, CB2 1QN, UK.
E-mail: dk465{at}cam.ac.uk

I would time travel to the ancient Mediterranean city of Syracuse to meet Archimedes, the Greeks' greatest polymath and preeminent engineer and teach him the design of an efficient steam engine. As the probable designer of such a highly creative and precision artifacts leading to the the Antikythera mechanism, Archimedes could apply steam energy technology to such computing devices, perhaps incorporating aspects of the Jacquard loom which would allow him to produce a more general purpose programmable computer. Judging from the astonishing construction of the Antikythera mechanism, I have no reasonable doubt that the technology required to build a larger steam powered computing device of somewhat limited programming capability could have been fashioned during this era. I would encourage Archimedes to travel to Alexandria in Egypt to perform demonstrations of the device, which would inspire the greatest intellects of the classical world and ensure the dissemination of this technology throughout antiquity in approximately 200 B.C.E. If this time traveling venture were successful, it would spur the Industrial Revolution and the advance of mathematics, lead to locomotion and world travel, and advance the state of the art in innumerable other fields. It might literally have advanced the planet's technology by more than 1500 years, and we might presently be colonizing the solar system and have reached Michio Kaku's level one technology.
Jeffrey L. Popplewell
Cincinnati, OH 45242, USA.
E-mail:jpopplewell{at}cinci.rr.com

I'd visit Alexandria, the "sanctuary" of ancient science, in the times of Hero, the first known inventor of the steam engine. This place at this particular time was crowded with the greatest minds of the ancient world. For information to really change something there is a need for people, which are able to perceive it, draw conclusions from it, and apply it. My idea is simple. Hero invented the steam engine but he considered it no more than a technological toy, thus I would show him that a machine working on the same principle generates usable power much greater than that of humans or animals. A usable steam engine would be a technological marvel predetermined to quickly spread through Rome's territory and benefit its economy. The first real Industrial Revolution would begin hand in hand with massive scientific progress. It is tempting to speculate that as a long-term result medieval age would never come and our knowledge would be laughable to scientist in the jubilee year 1000 C.E.
Peter Lenárt
Banská Bystrica, Bansko Bystrický kraj, 97401, Slovakia.
E-mail: divouspeter{at}gmail.com

I would travel to the first century C.E. to Alexandria and share with Hero of Alexandria the idea of the piston to turn his Aeolopile steam engine into more than just a spinning ball. Perhaps they would not understand this without algebra or Newton, but under the assumption they would, the Mediterranean culture of the time could have industrialized. Think of how things would be different today if all railroads led to Rome!
Alan Swartz
Vernon Hills, IL 60061, USA.
E-mail: aswartz{at}mail.roosevelt.edu

If I could travel back in time with one piece of scientific knowledge, I'd make it the human genome, along with the findings that all of humanity have common ancestors. Hence "race" is a meaningless distinction. I'd also say that we've had our modern anatomy for roughly 200,000 years. I'd go back to 310 C.E. and show all this to Constantine I in the hope that I could persuade him to take an even stronger line in the (then future) Edict of Milan on the lines of not merely tolerance of different religions, but intolerance of wars of conquest visited upon differing ethnic groups.
Joe Monterrubio
Osborne Park, WA, 6019, Australia.
E-mail: montysdouble{at}westnet.com.au

If I could share one piece of scientific information from today's world I would share the invention of the Internet and computers. I would go back to the early middle ages (12th century onward) and I would spread this information beginning with Europe, especially Rome. This information will serve to have an impact at many levels. First it will give the slaves an ability to unite against the practices of the slave trade. It will unite them under a common cause to raise their voice and prevent such "communal hatred." Second, it would help spread information quickly, which would make the Mongol invasions and the attack of Vikings less effective than they were at that time. Not only will this suppress slavery, but also change the whole world's politics. The world wars would be less destructive because of the "everyone knows everything" formula. There would be more cold wars but fewer real wars. The world would get to raise its voice against Hitler's genocide. The spread of medical facilities would become quick. Black Death could have been prevented. The spread and growth of technology would have been quicker, which would have helped Einstein confirm most of his theories. Ideas of Mahatma Gandhi and Nelson Mandela would have travelled far and wide. Above all, Mother Teresa's noble virtues would have perpetuated through time and geographies. Today we can solve most of our problems just by uniting the world.
Rishi Raj Sidhu
Department of Electrical Engineering, Indian Institute of Technology, Delhi, Hyderabad, Andhra Pradesh, 500032, India.
E-mail: rishirajsidhu{at}gmail.com

I would travel to the times of the bubonic plague in the Middle Ages where the poor knowledge of how diseases spread led to widespread uncontrolled infection. I would share knowledge about how diseases spread and consequently open the doors to methods that could contain the spread of diseases. It has the potential not only to minimize deaths in plagues, but also to prevent high numbers of casualties in future epidemics that faced mankind during the course of history and potentially in the future.
Bryce Tan
Department of Physiology, Yong Loo Lin School of Medicine, Singapore, 117456, Singapore.
E-mail: brycetan03{at}hotmail.com

Antibiotics could have rescued hundreds of millions of lives. The Nobel Prize in Medicine 1945 was awarded for the discovery of penicillin and its therapeutic effect. Nowadays, we are fortunate that various classes of antibiotics are available to treat a wide range of infectious diseases caused by bacteria. The bacterium Yersinia pestis has been responsible for several high-mortality pandemics throughout human history, including the severely devastating Black Death (originating in rodents) that accounted for the death of about one-third of the European population between 1347 and 1353. If time travel becomes possible, I would go back to Europe in 1345 (before the outbreak of the disease) and share with the medieval people our scientific knowledge about antibiotics, the technology for the production of antibiotic drugs, and how to use antibiotics properly, hence equipping them with the powerful tool to fight against the forthcoming plague. Consequently, hundreds of millions of people could have been cured. Although nobody really knows exactly what would happen if those lives were saved, an optimistic view is that the huge number of people who survived (and their descendants) would have greatly contributed to the advancement in every aspect of the society, leading to a much more developed world. Notably, there might be brilliant scientists, artists, inventors, and educators among the victims of the disaster. Some might even be geniuses who could have dramatically improved the quality of life of the people. If they were able to participate in promoting civilization, we should now be living in an unprecedented golden age that fantastically exceeds our imagination!
Chun-Wai Ma
Department of Physiology, The University of Hong Kong, Hong Kong, China.
E-mail: cwma2010{at}hku.hk

I would travel back to Sicily in October 1347 and explain how to manufacture attenuated vaccines against Yersinia pestis using formaldehyde produced by catalytic oxidation of methanol. Preventing the spread of the Black Death could have reduced religious fanaticism and persecution of minorities and maybe lead to an earlier and richer Renaissance.
Thierry Hennet
Department of Physiology, University of Zurich, Zurich, 8057, Switzerland.
E-mail: thennet{at}access.uzh.ch

Spain, 15 October 1447. I have travelled to this strange period where little is known about science and people cannot explain any more than they can see with their eyes. Narrow streets, where the last rays of sun are dissipated, led me to an old house where people were discussing around a cheese situated on a table. The butyric acid smell was present and I detected the "late blowing" defect ruining that cheese due to Clostridium spp. I decided to explain to the group of people: "There are living beings smaller than those our eyes can perceive, known as microorganisms, which are responsible for that undesirable effect. However, some microorganisms are responsible for the desirable transformation of bread or wine and they can be isolated and studied." This knowledge in the late Middle Ages might have led to a new era where people could have explained a phenomenon observed for ages: the fermentation process. Furthermore, this piece of knowledge could have led the discovery of enzymes and, even, relationships between microbes and disease might have been proved. The invention of printing in 1453 as well as the discovery of fermentation and microbes could have accelerated scientific revolution 200 years and many epidemic outbreaks could have been stopped in time.
Pedro Latorre
Department of Animal Production and Food Science, Universiy of Zaragoza, Zaragoza, 50013, Spain.
E-mail: pedro.latorre.muro{at}gmail.com

Scientific discoveries have shaped our history in both positive and negative ways. Sadly, faulty scientific theories have caused harm and even been used as justification for oppression. One of the most egregious of these theories has been scientific racism, which argued that people could be classified based on their physical characteristics into "superior" and "inferior" racial groups. This immoral, flawed science was used to justify horrendous atrocities, from slavery to genocide. Could these terrible events have been prevented if the perpetrators understood that their racial theories were scientifically groundless? I think that science was just one of many excuses used to rationalize these wrongs, and I doubt that that modern day scientific knowledge would have restrained the perpetrators. However, if society of the time believed that a person's intelligence, humanity, and moral character were completely independent of their race, perhaps people would not have supported leaders of racist movements and not stood for allowing these injustices to occur. That is why, to reach as many people as early as possible, I would go to the 1450s and use the newly invented printing press to share the knowledge that there is no scientific basis for racism. Scientific racism only played a small role in these tragic historical events, but its effects will still be felt for many generations. As we look towards the future of science, it is imperative for us not just to celebrate our accomplishments, but also to remember the worst mistakes of our past.
Alexandra Jazz Dickinson
Department of Chemistry, University of North Carolina, Chapel Hill, Chapel Hill, NC 27516, USA.
E-mail: adickins{at}email.unc.edu

I would travel to any major European city in the 1450s, world hubs of cultural change with long-lasting consequences. I would witness the trial of people accused of making magical pacts with the devil. These "witch hunts" would most likely target people from religious and ethnic minorities. In the collective imagination, witches cast spells that cause unexplained illness and crop failure. Listen and believe! Illnesses are not the product of magic. Many of these conditions are caused by trauma or poor nutrition. Infectious diseases already known to you are not triggered by "bad airs" channeled by unnatural powers, but by natural organisms called germs. By the way, folks, you can prevent many diseases by simply improving hygiene and reducing inbreeding. This brief exchange could potentially impact not only the health and medical history of humanity. But equally important, it could have implications for the future of social relations. It would represent a massive blow against bigotry in the western world. Back to the future, I would be just in time for the newly published NextGen Voices question: How were people in the 15th century convinced that time travel was possible?
Francisco Azuaje
NorLux Neuro-Oncology Laboratory, CRP-Sante (Public Research Centre for Health), Strassen, L-1445, Luxembourg.
E-mail: francisco.azuaje{at}crp-sante.lu

If I could travel back in time and share a piece of scientific knowledge that has influenced our history, I would definitely travel back to Leonardo da Vinci's epoch. Leonardo was a great inventor; he developed very interesting ideas such as the helicopter, the submarine, and even the car. Most of his projects were never built because they were not achievable at that time. I would really like to visit Leonardo and gift him the information that describes how to create the parts needed to realize the major projects he had in his mind. I'm sure that if we can combine Leonardo's great mind with the existing materials in our time, the course of our history would have changed significantly. Perhaps now instead of dreaming about the first human trip to Mars we would be developing "alien-like technologies" to visit parts of our universe beyond our solar system, as we see in science fiction movies.
Rigoberto Medina Andrés
Departamento de Bioquímica y Biología Molecular; Facultad de Ciencias, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, 62209, México.
E-mail: medina-ar{at}live.com

I would travel back to the time before the Spanish conquered Mexico in 1519. It is well known that apart from the Spanish language and Catholicism, the Spanish brought along contagious diseases. Mexican historians have speculated that smallpox was the main reason why the Aztecs succumbed to the Spanish conquistadors. The Aztec performed human sacrifices and suffered from several illnesses. In addition, when the Spanish arrived, they mercilessly killed thousands of natives. Nevertheless, death in battles came nowhere near the death by smallpox. I would take with me the wonderful smallpox vaccine and would show the Aztec how to vaccinate their people. This would have changed Mexican history forever! The Aztec empire would have never succumbed to the Spanish. I can imagine some changes deriving from that, such as the Spanish language becoming the second tongue in the country, and religion being a mix of Catholicism and polytheism. But the most important change would have been in the mentality of the Mexican people. Mexicans would not have a conflict of identity as they have always had (discussed in The Labyrinth of Solitude by Nobel Prize winner Octavio Paz). On the contrary, they would be self-confident citizens. Mexico would have stood up to countries like the United States and would not be a developing country as it is today. Who knows, it might even be one of the first-world countries! The smallpox vaccination would have prevented the fall of the Aztec empire and all its detrimental consequences.
Ivette Hernandez-Negrete
School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, B17 9RP, UK.
E-mail: inegrete{at}hotmail.com

To address the question, I thought "what essential side of science still has a long way to go?" I saw that most of the mysteries about microorganisms are yet to be discovered. They are precious tools in various study areas. So, sharing the knowledge about the significance of microorganisms with Antonie Van Leeuwenhoek would have been great for the gains in many fields of science and industry. Microbiology gives rise to a number of areas including biotechnology, biochemistry, genetics and molecular biology, production of chemicals, enzymes, pharmaceuticals, energy, food, and waste management. Although Leeuwenhoek found the equipment, he could not make the connection between these previously unseen forms and why milk became sour and how microbes caused diseases. It took about a century or two for scientists to put them together. Microbiology is still in its childhood. Early advances in the area would have saved countless material goods and specially, thousands of lives. If the knowledge had been there in the 1600s, by now we would have definitely known what all these 100 trillion bacteria do inside our bodies!
Ruwansha Samadarshi Galagedara
Department of Zoology, University of Colombo, Pannipitiya, Colombo, CO10230, Sri Lanka.
E-mail: ruwansha89{at}gmail.com

I backtrack to the late 1600s, precisely to the year 1687. In my readings, I find Isaac Newton to be one of the greatest minds of history. I would explain the atomic theory as known in the early 1900s. I would share with him how all matter had constituents, one of positive charge, one of neutral charge, and one of negative charge. I would explain the relative masses of each particle and their reaction with each other and how their structures make up the world as we know it. This theory wasn't even produced until Dalton's time, so the knowledge of the atomic theory 100 years before, in the hands of one of the most intelligent men to live, could produce a whole new revolution. If this information were given, the scientists that follow could build on this theory, and possibly the world that we live in now could have occurred 100 years ago. I think the full understanding of the atomic theory is what truly revolutionized our view of matter as a whole. The earlier this theory is discovered, exponentially more paths open for the future. Proposing this theory would save a couple hundred years of theorizing and experimenting. I believe placing the conception of this theory back in the days of Newton would place society far beyond the scientific knowledge that we have now. It would become a domino effect as more brilliant scientists and mathematicians such as Bohr, Rutherford, Einstein, and many others would be working on much more in depth theories than their time permitted.
Benjamin Robert Rathbone
Texas A&M University, San Antonio, TX 78216, USA.
E-mail: benjamin.rathbone{at}yahoo.com

I would travel back in time to Great Britain in the 1760s when the Industrial Revolution was just beginning. I would impart the knowledge of how solar and wind energy resources functioned and how they could be built. Although initially all the modern technologies that we use today would not be available, the enlightened thinking would be willing to work toward making wind and solar feasible in the late 1700s. Additionally, by allowing enlightenment thinkers consider renewable sources of energy, a new mindset might be built into the industrialization process and help demonstrate that sustainable energy solutions can protect the environment but also be more economically beneficial. Ideally, transforming the goals and designs implemented from the late 1700s until the mid-1800s would promote a more environmentally conscious society today and hopefully would have curbed the climate change crisis that we are currently facing.
Paul Andrew Di Salvo
Plainview, NY 11803, USA.
E-mail: padcrow{at}optonline.net

When looking at what we should change in the past, we must first look at what has the largest impact on our society and planet right now. For that reason, I would travel back to the beginning of the Industrial Revolution to revolutionize the idea of fuel and energy consumption, focusing on clean energy. I am no scientist yet, but I believe that a certain concept can be even more influential than a specific invention. What could our world look like right now if the Industrial Revolution had not started the spiral into environmental degradation? Surely we wouldn't have the reality of 26 billion tons of carbon dioxide discharged into the atmosphere annually. If some time traveler with an idea for Science magazine had gone and told the population at that time how large the impact of their actions would be, we could very well be on a path of sustainability and prosperity that has been relatively constant for generations. Speaking of prosperity, we have to keep in mind that this is not solely an environmental issue. Our world is increasingly focused on monetary value and global economics in this time when it is also changing at a rate faster than ever before. Currently, ecotourism is valued at several trillion dollars that could be drained from the global economy if landmarks like the Great Barrier Reef continue on the path they are on. There is no doubt in my mind that this one universally relatable concept is worth time-travelling for.
Sean Vallefuoco
Austin, TX 78726, USA.
E-mail: spv1015{at}sbcglobal.net

I would go to 29 May 1832, to talk with Évariste Galois. Like history says, one day later Galois would be involved in a duel, motivated by (still) questionable reasons, and should die. To change the history of mathematics, I just need convince him that the duel is absolutely the worst thing that he would do in his entire, and very brief, life. Indeed, even his last night before the duel was marked by an intense and brilliant work. If I would be able to convince him to he give up the duel, his future contributions to mathematics and physics would, of course, improve the science in several fields of knowledge.
Wagner Eduardo Richter
Institute of Chemistry, University of Campinas, Campinas, São Paulo, 13.083-970, Brazil.
E-mail: wagner.richter{at}iqm.unicamp.br

I would go to Falmouth, Cornwall, England on 2 October 1836. Once there, I would see the arrival of the HMS Beagle from its second journey around the world and wait for a 25-year-old Charles Robert Darwin to disembark. I would give him the most up-to-date edition of a Genetics textbook, and tell him to look for a Czech monk named Gregor Mendel that will (had?) publish(ed?) an important paper on pea hybridization 30 years later. Then I would take a photo of myself with the young confused Charles, buy myself a tasty Cornwall pasty, and time-travel away in my TARDIS, most likely to the Cambrian or Ediacaran periods to get me some animal samplings…
Jordi Paps
Department of Zoology, University of Oxford, Oxford, Oxfordshire, OX13PS, UK.
E-mail: jordi.papsmontserrat{at}zoo.x.ac.uk

If I could go back in time to share scientific knowledge, I would choose Africa in 1800–1900 and share with them advanced technologies and medical knowledge (vaccines, computer science, and robotic science). That info would change the shape of today's world. Africa would be the most advanced continent in the world when it would come to science. It would change the balance of power and the economy.
Safia Farah Djili
UJF Grenoble, Chambéry, Savoie, 73000, France.
E-mail: safiadjili{at}yahoo.fr

I would go back to the mid-19th century when hypodermic syringe was first invented in the world and share the knowledge that contaminated blood and body fluids could transmit blood-borne diseases. The transmission of some pathogenic viruses including HIV and Hepatitis B could have been reduced with the use of sterilized needle and disposable syringe. We would have minimized the risk of accidental exposures to patients receiving blood transfusion. Perhaps, there could be fewer people affected by the HIV/AIDS pandemic in the 1980s. According to the World Health Organization, AIDS has killed at least 35 million people worldwide and more than 34 million people are living with HIV today. Earlier education on the cause of the infection and ways to prevent transmission could have reduced the extent of the pandemic. In addition, knowing the disease mechanisms might have reduced stigma and encouraged more people to seek medical help and adopt a healthy lifestyle. With knowledge comes power, the government would then be empowered to introduce national measures including harm reduction strategies not only to prevent disease transmission but also to lessen stigma-related violence. Scientific knowledge about the cause and transmission of blood-borne diseases has transformed our lives. Although we cannot turn back time, we can learn important lessons from the past to create a better future.
Keng Gat Lim
Singapore, 132028, Singapore.
E-mail: kenggatlim{at}gmail.com

I would travel back to attend Michael Faraday's Bakerian Lecture to the Royal Society of London in 1857 and share the information that the size of Faraday's gold particles are in the order of nanometers—i.e., they are gold nanoparticles. The size and shape of these nanoparticles can be visualized by electron microscopies and their interactions with light—that is, the optical properties of the particles—are size and shape dependent as observed by Faraday. This might have given birth to quantum mechanics much earlier than we know and there might have been a "nanostorm" in the materials science and technology of 20th century. Probably effective ways of dealing with nanotoxicology would have been established by now.
Hari Krishna Bisoyi
Liquid Crystal Institute, Kent State University, Kent, OH 44242, USA.
E-mail: hbisoyi{at}kent.edu

The year is 1888. The place: Paris, France. That year, Élie Metchnikoff was given a position at the Pasteur Institute by Louis Pasteur. After hiding my time-machine, I took Metchnikoff to one of the Montmartre cafes. There, I explained to him that white blood cells express germ-line encoded receptors that specifically sense different infectious agents. In addition, I brought with me some KO cells, a portable fluorescent microscope and green-fluorescent protein-expressing bugs to perform a few experiments and demonstrate the proof-of-concept based on phagocytosis and killing of labeled bacteria. We prepared the bacteria growth media ourselves at the lab. He (and Paul Ehrlich, one of his opponents) did not believe me at first, but the data was pretty convincing and I did show them my pretty cool time-machine ride. They went nuts! This would have certainly changed the course of history given that new adjuvants, vaccines, and immune-therapies would have been discovered and tested in humans in the next 70 to 80 years after the scientific knowledge sharing.
Andre Bafica
Department of Microbiology, Immunology and Parasitology, Federal University of Santa Catarina, Florianopolis, SC 88040-970, Brazil.
E-mail: andre.bafica{at}ufsc.br

I would travel back to the 1890s, to Marie Curie's lab in Paris, France where she discovered two new elements polonium and radium. I would applaud her discovery of radioactivity and the treatments and techniques that have been designed as well as questions that have been answered using her discovery. I would most importantly express all she did as a woman in a time when men were superior. Marie overcame obstacles most of us are not familiar with today. She was unable to enroll in higher education due to being female. Marie pursued her studies in France and funded her discoveries not through the support of her university but rather through independent sources. She did not give up trying to establish herself when she returned to Poland to research, but was still turned away for being a woman. I would not only express what an impact Marie made on basic science research, but most notably inform her of the harmful effects of radiation that we now know about. This piece of information would not only potentially prevent an earlier death, but also warn others working with these radioactive elements. I'm not sure how knowing about the harmful effects of radiation on the body's health would change the course of history, but more lives could have lasted longer, allowing for greater discoveries to be made by remarkable scientists such as Madame Curie. Who knows how much further she could have advanced the scientific community if she had won two more Nobel Prizes.
Elizabeth Meredith
Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA.
E-mail: elizabeth.meredith{at}vanderbilt.edu

Paris, 1896, the center of European culture, modernity, and world trades. The society of that time was a direct observer of incredible changes in almost every aspect of life. Can one choose a more interesting place to travel back in time? I am waiting in one of countless Parisian cafes to meet with somebody special: Marie Curie. This ambitious first female doctorate student has just decided to study uranium rays for her thesis, work that will irreversibly change science, medicine, and technology in the near future. Surprisingly, Marie and her followers did not realize for many years how hazardous radioactivity is. I would like to share with her our current knowledge on how radiation influences our health. This knowledge will help her to avoid extensive radiation exposure. Moreover, with her authority, she will pursue the use of radioactivity in medicine in safer and better ways. This will save and improve lives not only of several scientists but hundreds of patients, workers, and soldiers who were exposed to considerable doses of radiation at the time when it was conceived to be a universal remedy and technological miracle. Going a little bit further, the early awareness of scientists and society about the risk associated with radioactivity could also potentially hold back nuclear weapon development. After this unusual meeting, I went to see the latest exhibition of my favorite post-impressionist paintings at Salon des Indépendants. This was very inspiring and unforgettable trip, but time to come back to 2013.
Magdalena Murawska
Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
E-mail: mmurawska{at}genetics.med.harvard.edu

I would go back to Detroit at around 1915 to 1916 to meet Henry Ford. I would tell him not to give up on the electric car design he has. I would encourage him to talk to Nikola Tesla because he has an alternative current motor design, and I would describe a hybrid engine to both. This will give electric and hybrid vehicles an earlier start leading to transportation dependent on much less or no oil today. As a result, we would have had cleaner air and much less carbon dioxide and lead in the atmosphere. The global temperatures would have been lower and due to less demand on oil there would have been fewer wars. This latter one is very personal for me because my brother and his wife were killed by a group of terrorists thriving in the Middle East due to instability of the region. In short, the world would have been a much better, slightly cooler place to live that I can share with my brother Cem and sister-in-law Dilay.
Bilal Ersen Kerman
LOG-Gage, Salk Institute, La Jolla, CA 92037, USA.
E-mail: bkerman{at}gmail.com

I would share the method of manufacturing the H1N1 flu vaccine with folks in 1915, giving them ample time to stockpile on the vaccine before the outbreak of the devastating Spanish influenza epidemic in 1918–19. Its influence on history would be modest; it would save a large percentage of the 40 million lives that were lost to the now infamous epidemic (although some estimates have put the death toll from that epidemic at 70 million). While not having adequate treatment or vaccine production capabilities might be considered the primary reason for the fatalities that resulted from the pandemic, it is also worthwhile to note that the mainstream "scientific" opinion of the time classified the Spanish flu as a bacterial rather than a viral infection. Apart from providing manufacturing instructions to produce vaccine against H1N1, it would also be useful to convince them about the viral origins of the disease and approaches to develop vaccines on their own should there be a mutant version of the flu virus that came up at a future date.
Bhavik Nathwani
Wyss Institute for Biologically Inspired Engineering, Harvard Medical School, Dana-Farber Cancer Center, Boston, MA 02115, USA.
E-mail: bhavik.nathwani{at}wyss.harvard.edu

9:00 a.m., 4 September 1939, blinked my chronograph. Hotel Waldorf-Astoria, New York, was hosting the Third International Congress for Microbiology. Fate had brought together the best minds of the time—Alexander Fleming, Gerhard Domagk, Selman Waksman, and Rene Dubos—future architects of the antibiotic era. The times were changing. Sulphonamides had arrived, penicillin was approaching trials, the Waksman lab was innovating discoveries, and evolutionary biology was emerging. Amidst lectures, I buttonholed the Chair, and despite his startled disbelief, was allowed to address the dignified audience. "I come from the year 2013. I represent no lab or organization, but the entire human race. The miracle of antibiotics you great minds will gift humanity has saved millions of lives. But today the world consumes 38 million pounds of antibiotics annually, and rampant misuse has saturated the planet's microbiome. Microbes are fast becoming resistant to all antibiotics, much like Dr. Fleming's experimental predictions. Thousands are dying of untreatable infections with no new antibiotics on the horizon. Antibiotic stewardship has impeded pockets of resistance, but is too little succor, realized too late. Amidst this dismal scenario is a vital piece of knowledge. Scientists have unraveled the microbial resistome, containing over 20,000 resistance genes which have been interacting and evolving with millions of antibiotic-like small molecules in our biosphere, since a billion years ago. This insight is encouraging non-reductive integration of evolutionary, chemical, and micro-biology to rethink antibiotics. I bring this knowledge to you pioneers, hoping to kindle ideas that will harmonize and make last the wonder of antibiotics."
Prashant Sood
Department of Hematology, All India Institute of Medical Sciences, New Delhi, New Delhi, 110029, India.
E-mail: drprashantsood{at}gmail.com

15 March 1941, Radcliffe Infirmary in Oxford, England. Albert Alexander has just died of sepsis after Howard Florey, Ernst Chain, and Norman Heatly were not able to provide enough penicillin to fully cure their first patient. I can offer an explanation as to how the bacteria were able to regroup, and at the same time a warning about underestimating their ability to develop resistance against the new miracle cure. If they can pass this information off as their own insight into what happened this day, future Nobel laureates Florey and Chain can spread this warning about antibiotic resistance much earlier than in our timeline. They might be able to influence politics by lobbying for strict control of antibiotic use in animal husbandry from the get-go. They could use their authority to advise against antibiotics in anything but confirmed bacterial infections and to warn about the ill effects of stopping treatment prematurely or slacking off with hospital hygiene. Heatly, on the other hand, could take this knowledge with him right to the important people at Merck when he stays there for several months starting December 1942, seeding there the need to keep looking for additional antibiotic compounds while the old ones still work. Patients will still need to comply with what these scientists tell them, and even then resistant Staphylococcus aureus will probably be found at some point. But when I come back to the present, hopefully there's more time left to keep finding new strategies against dying like Albert Alexander.
Eva Eismann
Würzburg, 97074, Germany.
E-mail: eva-e{at}gmx.de

I would like to go back to the year 1945, when Sir Alexander Fleming, Ernst Boris Chain, and Sir Howard Walter Florey won the Nobel Prize in physiology. The place is the Sweden. I want to talk about superbug with the three Nobel Prize winners. In 1945, penicillin has been widely used throughout the world. It was used without any limits. Almost everybody thought that penicillin can kill any kind of bacteria. However, I would tell them the existence of antibiotic resistance. There would be strong superbug which is resistant to all antibiotics. The existence of superbug is intimately related to antibiotic abuse, which causes evolution of bacterial DNA for better getting used to the environment. The people who were infected with superbugs would die of sepsis. Then, to make the people and the three Nobel Prize winners believe me, I would show some pictures and videos of the patients who are infected with superbugs. The patients are in great pain and there are no medicines to cure them, which would shock people. At the same time, I would convince them of antibiotic existence by showing them some experimental animals, which are resistant to the penicillin. I would tell them that the animals became resistant because of antibiotic abuse. If people in 1945 believed me, human beings would cut the use of antibiotics and would do research hard to prevent the occurrence of superbugs. Then there would be fewer superbugs and less antibiotic resistance and in 2013 we might not be essentially back to an era with no antibiotics.
Hongmei Dai
Central South University, Changsha City, Hunan Province, 410000, China.
E-mail: 1174561184{at}qq.com

If I could jump in the TARDIS and travel back in time, I'd go to Baltimore, MD in June 1951. More specifically, I'd go to Johns Hopkins Hospital to meet Ms. Henrietta Lacks. Around that time, she'd likely be undergoing radiation treatment for cervical cancer, but I'd hope that the story I'd tell her might brighten her day. Upon introducing myself as a time-traveling scientist, I'd tell her about how her biopsies would change the world. I'd explain how her cells, HeLa cells, helped improve human life by facilitating the development of the polio vaccine, anti-cancer drugs, HIV/AIDS treatments, and the like. I'd tell her that although people in her time believe that blacks are less than human, her cells would allow us all to understand that the human genome is organized into 46 chromosomes. During my time with her, I'd hope that she'd know the extent to which her suffering would bestow blessings to the world. Perhaps, her knowing this wouldn't change the course of history, but I bet many of us think in reviewing history, "Wow, if they only knew…" I believe Ms. Lacks deserved to know.
Brandi Sharp
Department of Biology, University of Virginia, Charlottesville, VA 22903, USA.
E-mail: bas7q{at}virginia.edu

The first time I read about this question, I could only think of one name: Rosalind Franklin (1920–1958). My essence as researcher and woman makes me wish to be able to run back into the past and run crazily in her laboratory at the King's College and alert her, "Beware Rosalind, avoid showing your DNA x-ray diffraction images to Wilkins (the famous photograph 51)." Wilkins, together with Watson and Crick, "inspired" by her finding, published in 1953 the structure of DNA and in 1962 won the Nobel of physiology and medicine. In each Nobel category up to three awardees can share the same prize. So, we still remain without knowing what would had happened if Franklin had lived longer. But I am sure that if she had foreseen what was going to happen, she would have avoided showing her amazing results to Wilkins. Rosalind Franklin deserves to occupy her place as an icon of the advancement of women in science. And probably today we would be studying the famous DNA model of Franklin.
Gina Pontes
Departamento de Biologia y Biodiversidad Experimental, Universidad de Buenos Aires, Buenos Aires, 1428, Argentina.
E-mail: ginapontes{at}hotmail.com

I would go back to the beginning of 2005 when I started my PhD and share with myself and my fellow PhD students the information about which research trajectories and which researchers would have been better to avoid or to follow, respectively. This would change the course of history in a way that would allow a handful of really great and excellent people with a huge potential to get the chance to fully develop this potential and give them a much better opportunity to a successful scientific career enabling them to solve some of the most fascinating and pressing questions in biology. Of course some of us will hopefully still do some of these things even if I don't go back, but who knows what possibilities were lost and are lost in the same way all the time?
Daniela Liebsch
Department of Forest Genetics and Plant Physiology, UPSC, Swedish University of Agricultural Sciences Umeå 901-83, Sweden.
E-mail: daniela.liebsch{at}slu.se

I would like to go back in the history of "one moment ago." My destination will be the "Planet Earth" to tell its people to save its environment in a scientific manner. Assuming that the people there will understand and believe me [as the question states], this will certainly refresh good deeds for the future universe. This refreshing will provide a second chance for a good beginning and will eventually increase the lifespan of a noble civilization.
Hamid Saeed Raza
Korea Advanced Institute of Science and Technology, Daejeon, 305-701, Korea.
E-mail: engg_hamidsaeed{at}kaist.ac.kr

Where technology is concerned, misanthropy subsists. I think that introducing a new technology to the past would result in disastrous consequences and is inherently unwise. If time educates without prejudice then we know from previous technological advances (such as the extraction of metals from their ores, gunpowder, atomic fission) that these advances not only improved the lives of people around the globe but that they were, without exception, used to destroy many of those people. This was the case even against the often better judgment of their creators and the scientific community at large. Evidently our technological advances to this point have not resulted in our destruction or the destruction of the planet (unless you count the slow destruction of both through global warming) and as such I would be tempted not to disturb this balance of scientific advance and social assimilation. It would be extremely easy to introduce a seemingly innocent and helpful technology to the people of the past and in the process give them the means to destroy each other. Furthermore, as these people did not develop the technology themselves, they would not yet have the social, moral, scientific or medical expertise in place to control this technology or cope with its effects. I would strongly resist the exchange of scientific knowledge with people of the past; almost certainly this is the wisest course of action, and as such may be why we have not received technology from the people of the future.
Roderick McKinlay Grieves
Centre for Cognitive and Neural Systems, University of Edinburgh, Edinburgh, Midlothian, EH8 9JZ, UK.
E-mail: krakenwaker{at}gmail.com