Saturday, November 19th, 2011

Neil deGrasse Tyson recently appeared on the “Ask Me Anything” page of Reddit and blew the minds of Redditors during an hour-long Q & A. Here are some of my favorite questions and the answers Tyson gave:

Q. If you could impress one thing on young people today, what would it be?

N.d.T. That adults are not all they’re cracked up to be. And most of them are wrong most of the time. This can be quite revelatory for a kid – often launching them on a personal quest of exploration, rather than of Q&A sessions with their parents.

Q. If you could add one course to a student’s curriculum, what would it be?

N.d.T. Course title every university should offer: “How to tell when someone else is full of shit”

Q. Can we inspire more kids to pursue space-related science and research? If so, how?

N.d.T. Kids are never the problem. They are born scientists. The problem is always the adults. The beat the curiosity out of the kids. They out-number kids. They vote. They wield resources. That’s why my public focus is primarily adults.

Q. What one improvement would you make to the way our society as a whole approaches science if it were within your power?

N.d.T. Society needs to see science not as a luxury of funding but as a fundamental activity that drives enlightenment, economics, and security. Science agencies should never have to go hat in hand to congress.

One idea would be for the USA (or any other country for that matter) to earmark 10% of its budget to R&D. Like a good startup company might do. That way everyone knows what to expect annually. And long term research projects will have some hope of funding stability.

Q. What is the simplest thing in your life that makes you happy?

N.d.T. Watching a person learn something new – not simply a new fact (those are cheap and easy) – but achieve a new understanding for how the world works. That’s the only reward a (true) educator ever seeks.

Q. What is your opinion about science/math education in high school? It seems to me like we emphasize far to much on facts that most people will never need, rather than encouraging people to think creatively and logically.

N.d.T. Agree 100%. Any time we are answer-driven rather than idea driven, we have lost the true meaning of education.

Q. What is your favorite fact about the Universe?

N.d.T. That it will never end. That it’s on a one way trip of expansion. Something that many find to be philosophically unsettling. My view is that if your philosophy is not unsettled daily then you are blind to all the universe has to offer.

My two very favorite exchanges I saved for last. I loved that Tyson answered this flip question with a very considered answer:

Q. If a taco and a burrito are traveling near the speed of light and collide, will the result be delicious?

N.d.T. The result would be an explosion large enough to destroy a small village. High speed collisions do that, whether or not they are made of Mexican food.

And the answer to this question is still blowing my mind:

Q. Since time slows relative to the speed of light, does this mean that photons are essentially not moving through time at all?

N.d.T. Yes. Precisely. Which means — are you seated?

Photons have no ticking time at all, which means, as far as they are concerned, they are absorbed the instant they are emitted, even if the distance traveled is across the universe itself.

This Q & A spawned a long discussion between dozens of Redditors, one of which attempted to explain the answer this way:

You can’t ascribe macroscopic analogies to quantum scale events. It doesn’t work because nature on that scale is so different than our everyday experiences.

To sum up the central point – photons don’t travel. They don’t really exist in flight. You can’t sidle up next to light passing from here to alpha centauri and watch it mid-flight. As soon as you do, it’s not in flight anymore.

What actually happens in reality is that an electron (or charged particle) over there will move in a particular way, and that makes an electron over here move in a particular way. Nothing else.

We can use a model based on waves to determine, probabilistically, where that effect is likely going to take place. We can also use a model based on particles (photons) to describe the nature of how that effect will act.

But it’s just a model. One must be extremely careful that we don’t ascribe other properties inherent in the model, such as existence, to the phenomenon being described.

The discussion ended (as much as a discussion such as this can end) with this poetic observation:

I love how existence can be a property that some things are capable of not having.

Tyson | 5:07 pm CDT
Category: Big Book of Quotations, daily drivel | Tags:
2 Comments | Add a comment

2 Comments

  1. 1 The Seanster said at 12:57 am on November 20th, 2011:

    “What actually happens in reality is that an electron (or charged particle) over there will move in a particular way, and that makes an electron over here move in a particular way. Nothing else.”

    That sounds similar to Orson Scott Card’s description of “philotes” in the sequels to “Ender’s Game.”

  2. 2 Dave said at 6:47 am on November 20th, 2011:

    Art imitates life. Wonder why Card didn’t just go with science, instead of science fiction?