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Physicists and Philosophers Debate the Boundaries of Science

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Re: Physicists and Philosophers Debate the Boundaries of Science

#11

Post by legulere »

Cyph0n wrote: post #4
Hermel wrote: post #2

If it is not testable, it does not sound like physics to me. Physics is an empirical science, and should therefore be testable by definition.

A large chunk of physics is theoretical in nature. Sometimes you simply cannot experimentally validate a phenomenon, so you instead propose a theory that attempts to explain it using physics. Then in the future, when the phenomenon is testable, your peers determine whether your theory was correct or not.

Atomism is a good example of how philosophy first made up a theory that was later confirmed (in a changed version).

https://en.wikipedia.org/wiki/Atomism

You could also derive the Atomic nature of matter through math though, as infinitely devisable sets end up with paradoxes that don't match up with reality (think banarch-tarski)

You can do all this without an idea how to test it.

Re: Physicists and Philosophers Debate the Boundaries of Science

#12

Post by alkonaut »

Cyph0n wrote: post #4
Hermel wrote: post #2

If it is not testable, it does not sound like physics to me. Physics is an empirical science, and should therefore be testable by definition.

A large chunk of physics is theoretical in nature. Sometimes you simply cannot experimentally validate a phenomenon, so you instead propose a theory that attempts to explain it using physics. Then in the future, when the phenomenon is testable, your peers determine whether your theory was correct or not.

Most times an experiment isn't possible/practical to perform, but the experiment could at least be described. The Higgs particle "If we build an accelerator that accelerates particles to energies pf X electron volts, we should see traces of it" must have sounded almost like a thought experiment when the Higgs boson was theorized. Same thing for e.g. the General Theory of Relativity and the Mercury passage that was one of the first validations of it.

Clearly if you propose a theory that requires an experiment so advanced (or circumstances so rare) we can't hope to do it in 20 years, it's still a valid scientific theory. What about 50-100 years? What if it requires technology so advanced it's nearly unthinkable that we will ever attain it? This is when it becomes a philiosophical gray area. It's not a clear cut case what is verifiable and what isn't, since the theory is valid before our ability to verify it.

Re: Physicists and Philosophers Debate the Boundaries of Science

#13

Post by shas3 »

wtallis wrote: post #10
Hermel wrote: post #2

If it is not testable, it does not sound like physics to me. Physics is an empirical science, and should therefore be testable by definition.

What do you mean by "testable"? There's a pretty big spectrum of "untestable" ranging from requiring too many trillions of dollars to requiring more resources than this planet has to requiring equipment or energy levels we don't know how to produce even in theory to requiring stuff we're pretty sure is impossible like looking beyond the range of the observable universe or requiring more energy than is contained in th…

You've actually summarized the article in your comment!

Re: Physicists and Philosophers Debate the Boundaries of Science

#14

Post by cwzwarich »

Hermel wrote: post #2

If it is not testable, it does not sound like physics to me. Physics is an empirical science, and should therefore be testable by definition.

Cosmology has been an uncontroversial part of physics for quite some time now, and most of its major claims can never be tested in the same that other physical theories can be tested, barring some "creation of a universe in a lab" scenario.

Re: Physicists and Philosophers Debate the Boundaries of Science

#15

Post by Animats »

Physics used to be "hard science" - if it wasn't testable, it wasn't meaningful. Physicists used to look down on other sciences for that reason. This article shows how much worse things have become. Nobody can figure out a way to test string theory. In cosmology, you can only observe, not experiment. As the article points out, the big questions are out of reach for scaling reasons.

Trying to fix the problem through weaker definitions of "testable" is desperation. All those smart people hate to face the fact that what they're doing may be total bullshit. This has major economic consequences for physicists - why should they be funded? Physics is funded because it produced the atomic bomb and semiconductors. Those came from the testable parts of physics. Untestable physics cannot produce engineering technology.

(The article says "no one has ever seen an atom". That's just wrong. There are lots of picture of atoms. Even pictures of atoms lined up to spell "IBM".[1])

[1] http://www.nytimes.com/1990/04/05/us/2-researchers-spell-ibm...

Re: Physicists and Philosophers Debate the Boundaries of Science

#16

Post by weinzierl » 

    Nowadays, as several philosophers at the workshop said, 
    Popperian falsificationism has been supplanted by Bayesian 
    confirmation theory, or Bayesianism, a modern framework 
    based on the 18th-century probability theory of the English 
    statistician and minister Thomas Bayes. Bayesianism allows 
    for the fact that modern scientific theories typically make 
    claims far beyond what can be directly observed — no one has 
    ever seen an atom — and so today’s theories often resist a 
    falsified-unfalsified dichotomy. Instead, trust in a theory 
    often falls somewhere along a continuum, sliding up or down 
    between 0 and 100 percent as new information becomes 
    available. “The Bayesian framework is much more flexible” 
    than Popper’s theory, said Stephan Hartmann, a Bayesian 
    philosopher at LMU. “It also connects nicely to the 
    psychology of reasoning.”
I've never heard of Bayesianism in this context. Is this a serious approach in the philosophy of science?

Re: Physicists and Philosophers Debate the Boundaries of Science

#19

Post by LoSboccacc »

burke wrote: post #8
taylored wrote: post #3

Earlier quoted context omitted.

Its testable just not with current tech

Maybe not. It's not completely clear that, for example, string theory could ever be experimentally verified, since it operates completely at a level below all the manifestations of our observable universe. (AFAIK, I'm no physicist) What technology can you imagine that could ever prove or disprove a hypothesis of our universe being only one facet of a multiverse? The apparatus would necessarily exist within the closed…

> The apparatus would necessarily exist within the closed system.

does being in a multiverse influences our world in any way using current theories?

yes > we can eventually figure out and run an experiment no > then studying it is as productive as searching the Russel's teapot

this is how you set apart a theory from speculation, a falsification test. i.e. > http://arxiv.org/abs/1210.1847

Re: Physicists and Philosophers Debate the Boundaries of Science

#20

Post by weinzierl »

Animats wrote: post #15

Physics used to be "hard science" - if it wasn't testable, it wasn't meaningful. Physicists used to look down on other sciences for that reason. This article shows how much worse things have become. Nobody can figure out a way to test string theory. In cosmology, you can only observe, not experiment. As the article points out, the big questions are out of reach for scaling reasons. Trying to fix the problem through w…

I fully agree with your point, but I think the "picture of atoms" is not a good supporting argument. The IBM image[1] is nothing more than a visualization of measurements including a good measure of artistic license. It has not much to do with seeing in the usual sense.

[1] http://researcher.watson.ibm.com/researcher/files/us-flinte/...

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