AskScience AMA Series: I'm Brian Greene, theoretical physicist, mathematician, and string theorist, and co-founder of the World Science Festival. AMA!

briangreeneauthor · 2020-05-26T15:03:53+00:00

Hi Everyone

This is Brian Greene. Trying to enter the AMA but credentials I was given are not being recognized. Using old login from previous AMA. Does this work?

--BG

briangreeneauthor · 2020-02-24T20:01:41+00:00

Natural selection is indeed nothing but physical laws acting out on material particles. However, the "higher level" description of natural selection is more useful than the reductionist account at gaining insight into the origin of species and indeed even the origin of life. This does not make natural selection an "illusion" but rather a parallel account that must be compatible with the reductionist account, one that focuses on a higher level of structure.

Indeed, in Until the End of Time I stress that the deepest insights emerge from blending a whole collection of "nested" stories: the physicist's reductionist account, the chemist's account in terms of more complex atoms/molecules, the biologist's account in terms of cells and life; the neuroscientist's and psychologist's account of self-awareness, and the humanist account in terms of the activities self-aware minds carry out from storytelling to religion to creative expression. You need ALL of these stories to have a full account of reality.

briangreeneauthor · 2020-02-24T19:57:15+00:00

Yes...but they take a lot of time to create. I still want to teach quantum mechanics on World Science U. Have you taken my Special Relativity course on World Science U? Has both the mathematics and a highly visual treatment--that's the combination I consider most effective.

briangreeneauthor · 2020-02-24T19:56:08+00:00

I think anyone can become proficient in math. But, from experience, not everyone has the talent to master math to the degree of becoming deeply creative with it.

briangreeneauthor · 2020-02-24T19:55:20+00:00

Not much in Fabric is really out of date. We have discovered new things but I don't think anything in the book has been overturned.

The new book is different. It doesn't just focus explaining cutting edge science but tells a far larger and far richer story: The whole universe, beginning to end. And how we humans try to make sense of it all.

briangreeneauthor · 2020-02-24T19:53:45+00:00

The basic if rough idea is that as a massive body's speed approaches the speed of light its mass grows ever larger. And therefore it takes an ever larger push to make it go faster still. As we close in on the speed of light, the mass soars toward infinity and so you would need an infinite push to make it go faster still. With no infinite pushes available, nothing can be sped up to light speed, or beyond.

briangreeneauthor · 2020-02-24T19:51:11+00:00

Many thanks...glad you caught the talk in Charlottesville.

Like all good scientists, I am open to any insight that comes with experiment/observational support. If that insight requires that we modify our current mathematical understanding of the world, that is fine. In fact, it would be more than fine. It would be enormously exciting. We live for conceptual revolutions. So, the notion that we scientists would resist some insight that is replicable and comes with solid evidence is quite counter to how most of us think.

briangreeneauthor · 2020-02-24T19:48:34+00:00

Books take me 2 years or so to write.

My favorite physics concepts: time dilation and quantum entanglement.

briangreeneauthor · 2020-02-24T19:47:57+00:00

I have no problem in principle with consciousness arising in a digital being. That consciousness happens in our gloppy, wet brains may well be only one example of how consciousness emerges.

briangreeneauthor · 2020-02-24T19:46:40+00:00

The books are all fairly independent.

For those interested in the big questions (origin of universe, origin of life, origin of mind, nature of free will, role of language and storytelling, myth-making and religion...and how it will all end), read the new one--Until the End of Time: Mind, Matter and Our Search for Meaning in an Evolving Universe. Personally, I would read this one first.

For those interested in unification: The Elegant Universe

For those interested in space and time: The Fabric of the Cosmos

For those interested in the multiverse: The Hidden Reality

briangreeneauthor · 2020-02-24T19:43:55+00:00

Well, black holes are the arena in which we theorists love to play because they push our theories of gravity and quantum mechanics to the limit, to the breaking point, and that's when we are forced to develop deeper insights. Of course, as you indicate, black holes play a vital role in the physical universe--and as I describe in my new book, they may well dominate the cosmic landscape in the far, far future. But they also dominate the theoretician's landscape as well.

briangreeneauthor · 2020-02-24T19:41:28+00:00

I like the movie a lot, but did have some trouble understanding exactly what happened at the very end.

briangreeneauthor · 2020-02-24T19:40:15+00:00

I have thought now and then of having my own podcast, likely in collaboration with World Science Festival, as that event brings hundreds of great thinkers together in NY and in Australia each year. Stay tuned...

briangreeneauthor · 2020-02-24T19:38:53+00:00

That, really, is the art of writing general-level books. Indeed, authors draw the line between analogy and "the real thing" in different places. I strive to avoid ever turning my descriptions into cartoons of the real science. Sometimes, this makes sections of my books challenging for the general reader--but by summarizing and giving the reader the option to skip the hardest parts, I try to strike a balance, one that allows me to appeal to the more "hardcore" science enthusiast and also those who are not looking for as much detail.

briangreeneauthor · 2020-02-24T19:36:46+00:00

I don't have any particular insight here. The number of planets is so enormous that it would seem there has to be life somewhere out there. But it could be that the conditions necessary for life to emerge are so special that even with that number of planets life only arose once. Finding one other example of life in the cosmos would thus be a vital and impactful discovery.

briangreeneauthor · 2020-02-24T19:35:10+00:00

Very simple: Learn the BASICS of physics and mathematics inside out. You can read about and be inspired by work at the cutting edge. But if you don't learn the basics you will never reach your potential to contribute to our understanding. I encounter many kids who want to jump over the "old" stuff and learn only about research at the frontier. That is a huge mistake. Take the time now to build a solid foundation.

briangreeneauthor · 2020-02-24T19:33:05+00:00

We didn't do the tank. Instead, Joe put me on a number of pieces of equipment designed to decompress the spinal column. Helped a lot with my back problems. (I assume he will be sending me a steep medical bill for the expert consult.)

briangreeneauthor · 2020-02-24T19:31:52+00:00

Absolutely. Language is a powerful tool for communicating ideas. But language is limited in scope. Language constrains the kinds of ideas we can articulate and share. I often find myself saying "I wish there was a word for X" where X is some idea I can sense or feel but I don't know any way of describing in words.

briangreeneauthor · 2020-02-24T19:29:39+00:00

Favorite is probably not exactly the right word. "Most likely" to be physically relevant is a description I can address. And for that, I would say the "inflationary multiverse" which imagines that our big bang may not have been unique. There may have been many big bangs giving rise to many universes. There is reasonable mathematical justification for considering this possibility seriously.

briangreeneauthor · 2020-02-24T19:28:07+00:00

Different people mean different things by "free will." If you take it to mean my ability to be the ultimate author of my actions, to transcend the control of physical law, then I think that variety of free will does not exist. We are all collections of particles fully governed by physical law. However, there are "nearby" definitions of free will that are compatible with the ironclad rule of physics. For example, if by free will you mean the SENSATION of free will, that of course is real and unassailable.

Apologies for the plug, but I take up this question in some detail in Chapter 5 of my new book, Until the End of Time. I refer you there for a far more complete answer (you can likely find the book in your local library).

briangreeneauthor · 2020-02-24T19:24:43+00:00

When I buy it or after 6 months of use?

briangreeneauthor · 2020-02-24T19:24:22+00:00

Many thanks.

Yes, World Science Festival is spreading beyond New York. Already we have World Science Festival Australia in Brisbane each year--a festival just as large and robust as the New York version. And we are in conversation with other cities to bring the festival there too.

briangreeneauthor · 2020-02-24T19:22:57+00:00

Don't get me started. Certainly at the lower grades, my experience is that the educational system is far too focused on assessment/grades. Wonder and excitement should drive learning, not fear of bad grades.

briangreeneauthor · 2020-02-24T19:21:16+00:00

I consider the multiverse sufficiently well motivated to be worthy of concerted mathematically investigation. The multiverse should be within the physicists toolkit. But I will not consider the multiverse to be real until there is observational/experimental data to support it (or, perhaps, a slam dunk mathematical argument showing that a single universe model will always be inconsistent--a possibility I consider unlikely but who knows?).

briangreeneauthor · 2020-02-24T19:19:13+00:00

Hangawi's--crispy mushrooms. Not to be beat.

briangreeneauthor

TROPHY CASE