Cosmos: A Spacetime Odyssey

[Phoenix Wright]

Don't mathematical physicists make the most contributions nowadays, for example in string theory? That's all from the armchair

"mathematical" physicists? and no, not even close.

string theory is not the forefront of scientific discovery. it is wishful thinking with basically no evidence.

[Chiki]

"mathematical" physicists? and no, not even close.

string theory is not the forefront of scientific discovery. it is wishful thinking with basically no evidence.

You don't sound like a good scientist. So what if it has no evidence? General relativity took dozens of years to prove. It just means we don't have the technology required.

NOVA: How likely do you think it is that string theory will be proven correct?

Witten: Well, I don't have a crystal ball. You know, the theory of neutron stars was tested and the same is true of the theory of black holes and the theory of gravitational waves. A lot of the theories that were there in the '20s and '30s that looked like they were way beyond reach were eventually tested. They were tested because there were new technologies, there were new instruments, there were newer things found in the sky. Things happened that you couldn't foresee. That's what happens in science.

NOVA: Do you think it's possible that string theory will turn out to be wrong, or at least some branch of knowledge that just isn't connected to nature?

Witten: I guess it's possible that string theory could be wrong. But if it is in fact wrong, it's amazing that it's been so rich and has survived so many brushes with catastrophe and has linked up with the established physical theories in so many ways, providing so many new insights about them. I wouldn't have thought that a wrong theory should lead us to understand better the ordinary quantum field theories or to have new insights about the quantum states of black holes.

And it doesn't make it any less useful even if it's wrong. There's a lot of ultimately mistaken theories that helped lead us to the truth, for example, Newtonian mechanics.

[Phoenix Wright]

You don't sound like a good scientist.

oh?

So what if it has no evidence?

ha. anyway,

General relativity took dozens of years to prove. It just means we don't have the technology required.

And it doesn't make it any less useful even if it's wrong. There's a lot of ultimately mistaken theories that helped lead us to the truth, for example, Newtonian mechanics.

great point. science is built on mistakes. but more importantly, it is built by evidence. and for as long as string theory is purported as the "forefront of physics," i, in addition to many other actual scientists, will shoot it down. what proponents such as witten himself have said is that the pursuit of a proper theory is basically impossible. since its inception in 1969, none of its theoretical mathematics have been tested.

i do not reject string theory because it has not been tested, but because it essentially cannot be tested. perhaps technology will allow us to test it later; i'm excited for those times, given i'll be alive to see it. there's a discontinuity in the current physical model that we have no real way of rectifying as of yet. i yearn for the days where we can actually test those new theories.

Edited May 31, 2014 by Phoenix Wright

[Chiki]

but because it essentially cannot be tested.

To say essentially means to say that it never, no matter the technology, can be tested.

NOVA: It seems like the standard criticism of string theory is that it isn't testable. How do you respond to that criticism?

Witten: One very important aspect of string theory is definitely testable. That was the prediction of supersymmetry, which emerged from string theory in the early '70s. Experimentalists are still trying to test it. It hasn't been proved that supersymmetry is right. But there is a very precise relationship among the interaction rates of different kinds of particles which follows from supersymmetry and which has been tested successfully. Because of that and a variety of other clues, many physicists do suspect that our present decade is the decade when supersymmetry will be discovered.

Edited May 31, 2014 by Chiki

[Phoenix Wright]

NOVA: It seems like the standard criticism of string theory is that it isn't testable. How do you respond to that criticism?

Witten: One very important aspect of string theory is definitely testable. That was the prediction of supersymmetry, which emerged from string theory in the early '70s. Experimentalists are still trying to test it. It hasn't been proved that supersymmetry is right. But there is a very precise relationship among the interaction rates of different kinds of particles which follows from supersymmetry and which has been tested successfully. Because of that and a variety of other clues, many physicists do suspect that our present decade is the decade when supersymmetry will be discovered.

an interview from 2003! my, where did the decade go...?

from wikipedia:

The failure of the Large Hadron Collider to find evidence for supersymmetry has led some physicists to suggest that the theory should be abandoned as a solution to such problems, as any superpartners that exist would now need to be too massive to solve the paradoxes anyway.

it's not a little bit interesting how this panned out. that's not to say i'm happy about the results, because string theory is pretty darn cool, but it's an untestable theory. at least for a while.

excuse my misuse of the word, if i did in fact misuse it.

[dondon151]

This is complete crap. People like David Chalmers, Richard Montague and Noam Chomsky etc. are/were leaders in cognitive science and formal semantics and syntax, respectively. Arguably the hardest problem in science (the problem of consciousness) is, ironically, mainly tackled by philosophers, though some scientists like Giulio Tononi have important contributions too.

are those physical sciences? i'm pretty sure they aren't, according to the categorization provided on wikipedia.

i think philosophy is a fine tool when it comes to making hypotheses about abstract concepts, but it's plainly unscientific past a certain point. i don't mean to misinterpret NDT if this is in fact not what he means, but my impression of his stance is that time spent arguing is better spent testing.

Edited May 31, 2014 by dondon151

[Chiki]

are those physical sciences? i'm pretty sure they aren't, according to the categorization provided on wikipedia.

i think philosophy is a fine tool when it comes to making hypotheses about abstract concepts, but it's plainly unscientific past a certain point. i don't mean to misinterpret NDT if this is in fact not what he means, but my impression of his stance is that time spent arguing is better spent testing.

They're physical sciences in the same sense that mathematical physics is a physical science. Both attempt to describe physical phenomenon in mathematical terms. Syntax, for example, is the study of what computations actually go on in the brain when someone tries to make a sentence--or at least an attempt to create a formal system which accurately characterizes those computations.

Edited May 31, 2014 by Chiki

[dondon151]

They're physical sciences in the same sense that mathematical physics is a physical science.

i presume that phoenix wright earlier sarcastically remarked "mathematical physics" because there is no such distinction between mathematical and non-mathematical physics, if the latter even exists. you also said earlier that philosophy has had no contribution to physics in the past 100 years.

Both attempt to describe physical phenomenon in mathematical terms. Syntax, for example, is the study of what computations actually go on in the brain when someone tries to make a sentence--or at least an attempt to create a formal system which accurately characterizes those computations.

syntax isn't a physical science. it falls under the umbrella of social science -> linguistics.

EDIT: literally what google spits out when you search for "what is physical science:"

phys·i·cal sci·ences

noun

noun: physical science

1. the sciences concerned with the study of inanimate natural objects, including physics, chemistry, astronomy, and related subjects.

Edited May 31, 2014 by dondon151

[Chiki]

Ok, I thought physical science was just the study of natural objects,, whether animate or inanimate. I agree with NDT in that case, if he only meant physics, chemistry and so on. But I think NDT meant both biological and physical sciences when he said physical sciences:

t's not that there can't be other philosophical subjects, there is religious philosophy, and ethical philosophy, and political philosophy, plenty of stuff for the philosophers to do, but the frontier of the physical sciences does not appear to be among them.

He doesn't seem to mention any contributions in the biological sciences, which seems pretty important since it's a science, after all.

Edited May 31, 2014 by Chiki

[dondon151]

i think it really depends on which part of the life sciences you're thinking about. i doubt philosophy has much to do with the study of animal behavior, plants, and so on, given how they don't think like us (or at all) in the vast majority of cases. similarly, disciplines such as biochemistry and cell biology are pretty much variations on physical science. the only disciplines within the life sciences in which i think philosophy might be important are neuroscience and sociobiology.

Edited May 31, 2014 by dondon151

[Chiki]

The most controversial debates in cognitive science don't focus on humans per se. One of the main questions cognitive scientists are interested in answering is "how do animals have sensations?" It's an almost impossible question to answer, and the hardest meaningful question in science. Imo it's essentially impossible to answer.

Edited May 31, 2014 by Chiki

[Phoenix Wright]

Wow.

that's all i can say, really. i knew ep. 12 (and likely 13) would be one of my favorites.

[RJWalker]

Oh man, the final scenes from the final episode were genius. Brilliant.