The future of physics

Leave a comment

So, if you’re like me and you watched Brian Greene’s TED talk on string theory, you probably wonder how experiments on little strings vibrating in curled-up dimensions will affect our daily lives. In fact, there are plenty of ways, detailed in this list of how physics will change the future.

The first time I heard about the useful application of quantum mechanics was in the field of cryptography. As we store more and more of our personal information online, it’s that much more important for this data to remain well-encrypted. The race between code makers and code breakers has been close through the ages, but the cryptographers may finally win with the help of photons. Once quantum key distribution becomes the norm, it will be impossible for hackers to get into a system without announcing their presence, thereby defeating their purpose.

Quantum dots latched on to cancer cells

Cancer cells might not be able to go undetected anymore, either. Quantum “dots,” tiny semiconductor crystals, glow when exposed to ultraviolet radiation and, when coated with the right substance, latch on to cancer cells. Doctors can then pinpoint exactly which cells to target with treatment while leaving the rest of the healthy cells alone.

Meanwhile, in Brazil, scientists are using quantum physics to replicate turbulence in the lab so that someday we may be able to predict the chaotic swirls in gas and liquids. Flights will become smoother and weather reports more reliable.

But then again, if you want to just skip the security lines altogether you can always invest in transportation research. Scientists have been able to scan molecules and reconstruct them elsewhere…but don’t recycle your 3 oz liquid bottles yet: these aren’t exact copies of the molecules, they are twins. In the process of teleportation the original is destroyed. Sound like a good plot line? It’s already been done; beautifully, in my opinion, in 2006’s The Prestige (it’s a great movie so if you don’t want the ending ruined don’t watch the following clip):

A billion heartbeats: On time

Leave a comment

Time is such an integral element in our lives sometimes it’s hard to imagine it as a matter of debate, a dimension that is both exact and yet able to be perceived in multiple ways. I recently read an incredible list of facts we should all know about time. Here are the most interesting elements:

Time exists–this is certain. A little over a century ago, though, Einstein put forth his theory of relativity which distorted Newton’s classic physics model and thereby the previously accepted understanding of time. Einstein explained that times elapses differently near the speed of light and near black holes. No, most of us will not experience the passage of time in these circumstances, but we’re all familiar with the sensation that time starts to speed up as we get older. And indeed this phenomenon is representative of time being experientially relative.

And yet we are so dependent on time that it influences our cognitive development, communication, and decision processes. The ability to imagine alternative outcomes was necessary for early survival, while our linguistic tenses allow us to discuss these possibilities as a group.

Speaking of possibility, I had the epiphany in high school that all future events must be probabilistically implicit in the present moment. That is, every large and small event that happens in the future (whether I have a child several years down the road or whether I’m late to work tomorrow) will follow a discrete chain of occurrences, each one following the last because it is statistically possible. Granted, the probabilities of each event are infinitesimal past the events that happen in the next few minutes (whether I get up and refill my glass of wine or play my next move in Words With Friends), and yet they are there. (By the way, I just refilled my glass of wine and now there’s a slightly greater chance that I will be late for my 8 am meeting).

Why is this important? Because of this: the past and future are equally real. Whoa.

But what about the present? Our brains delay our experience by 80 milliseconds, about the blink of an eye, so as to compile the “present moment.” It was only after Janet Jackson’s halftime nip-slip that television broadcasters realized why this is important (who knows what hijinks Madonna would have gotten into during today’s Superbowl if we weren’t on a delayed broadcast). When I read this fact, I wondered if this aspect of consciousness has anything to do with flow, the mental process that artists and athletes describe that circumvents usual perception of time. If your muscles respond before you need to think how to react, does that 80-millisecond lag time get reduced? And if so, does that contribute to the sense that time is slowing down?

Having a heart to heart

Whether we live in the past or accept the future as real, though, time moves forward and so does the natural process of aging. Indeed, there are many scientific experiments in the works that may extend human life, and we have already increased lifespans through modern medicine and decreased threats such as predators, exposure to the elements, and other stressors common to early mankind. Yet studies show that the average number of heartbeats for any complex organism is constant, so long as it is not killed prematurely. The larger a creature is, the more efficiently its cells metabolize, the slower its heart, and the longer it lives. There’s a relatively simple scale that shows the magnitude of all these factors, which shows that each one of us, from hummingbird to elephant, has about 1.5 billion heartbeats.

If we only have a billion heartbeats then, let’s not waste them on worrying about what has happened or what may happen in the past, present, or future. Time to refill that wine glass once more.

How to be a quantum physicist

Leave a comment

What You’ll Need: rules, the desire to break rules

Songlist: I’ve Got the World on a String by Frank Sinatra, Cat’s in the Cradle by Harry Chapin

Further reading: Physics and Beyond by Werner Heisenberg, The Making of the Atomic Bomb by Richard Rhodes

Shoot, I forgot to carry the 1!

Caveat: I don’t even completely know what a quantum physicist does. I dropped out of Physics 101 in my senior year of high school to take Painting 101. But that same semester, as I was working my way through the color chart and learning the difference between hue, tint, shade, and tone, a principle first proposed in 1927 came along and blew my mind.

Heisenberg’s Uncertainty Principle: “One can never know with perfect accuracy both of those two important factors which determine the movement of one of the smallest particles—its position and its velocity. It is impossible to determine accurately both the position and the direction and speed of a particle at the same instant.”

What Heisenberg introduced was not just a paradox in the scientific community, but a profound epistemological problem. While the modernist age in which he worked was based on the certain progress of man via industry and art, Heisenberg did his part to usher in post-modernism by proving a limit to knowledge, and thereby a limit to progress. At some point, there are things in the universe that are simply unknowable by humankind.

Theoretical physics is one of the most philosophically rich and morally challenging fields of our time. I’m currently reading Richard Rhodes Pulitzer Prize-winning The Making of the Atomic Bomb, an incredible history of early twentieth century science. It’s strange to realize that only a hundred years ago, the atom was a debatable concept. And over the course of only a few decades, the atom became a weapon of catastrophic potential. Scientists working on the atomic bomb in the United States weren’t even sure if they would be able to harness its power–some worried that a self-sustaining atomic reaction would consume the entire atmosphere, effectively blowing up the planet Earth.

When scientists began work on what was later known as the Manhattan Project, the motivation seemed as much to defeat the enemy as to continue working in what Rhodes (via a chemist, Polanyi, who also studied the process of science) refers to as the “growing points”–the place where the most productive discoveries were being made. Heisenberg himself talks about this in his book Physics and Beyond: he was naturally attracted to physics because the greatest discoveries in the world were all in that field, whereas if he’d been born contemporaneously with Mozart he might have ended up a composer.

Yeah, this makes sense as a theory of the universe...

In the past century, the general theory of relativity (proposed by some obscure scientist named Einstein) redefined the scope of physics and led directly and indirectly to the many-worlds interpretation, which postulates that all possible outcomes in any given situation simultaneously occur in a multiverse of independent parallel universes; to spacetime singularities, where the paths of light and particles come to an abrupt end in the universe; to quantum teleportation, which seeks to transmit quantum information over arbitrary distances; to string theory, which posits many unknowable dimensions in addition to the four we are able to experience; to M-theory, a theory so complex and esoteric the scientists themselves who are working on it don’t agree what the “M” stands for. As American physicist Richard Feynman said, “I think I can safely say that nobody understands quantum mechanics.”

Einstein himself was disturbed at the growing ambiguity and loss of measurement in physics. He famously stated, “God does not play dice with the universe.” Which is precisely what’s so interesting in twentieth and twenty-first century physics. Are we getting closer to the truth, or have we come to a barrier of knowledge beyond which no human can pass?