Thread: About the world within? Effects on Time of Speed of Light Travel.

Originally Posted by megafiddle

But isn't that also true with a physical experiment?

For sure. Science usually advances by debunking old theories.

But a thought experiment doesn't offer any mechanisms to be tested through another thought experiment. It is a construction that is purposely made valid according to available knowledge. As such, in its time, it is always true and never false. What will determine its falsehood is new knowledge gained from hard science. A scientific theory, on the contrary, requires will be evolved or debunked through another scientific theory. The scientific method is built to oversee itself.

Originally Posted by megafiddle

Is it possible to construct a thought experiment that is so simple, that the result would be accepted a priori as scientific fact?

Such a thought experiment would be unnecessary. What manner of new scientific knowledge could we gain from a simple logical device? If something new is so obviously true, then we don't need an abstraction to test and validate it. It just is true by sheer deduction.

Is it possible to construct a thought experiment that is so simple, that the result would be accepted a priori as scientific fact?

Can you give us an example?

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I should add that I'm after a new scientific fact, not just establishing that your "thought experiment" is a variation of another scientific fact.
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Originally Posted by Yarin

It's an observed concept. I imagine trying to test it would produce far less promising results than said simple observation of it. This seems to hold true for any stance on qualia.

Right. The God theory. You cannot prove it false, so it must be true.

Anyways, no it is not an observed concept. It can only be partially observed and because of the very nature of its formulation, cannot be proven true. Cognitive Closure is an absolute nonsense that has the good sense of remaining to this day a philosophical hypothesis. Check your facts.

Originally Posted by Yarin

Even if the evolution you speak of was true, closure would still hold true because said evolution isn't driven by ourselves.

And who by then? Nature (whatever It may be)? God? Aliens?

Evolution is strictly dictated by ourselves. I suggest, if Charles Darwin is too complicated of a reading, you read Mount Improbable by Richard Dawkins, author of The Selfish Gene. An even better reading, but more difficult.

As for the evolution I speak of being true or not, I'm assuming you are not a Creationist and you just referring to the fact we may not evolve in the direction I wished.

Well, there's very little doubt in my mind that one of the organs in our body that has a whole lot more evolving to do is precisely our brain. Unless you think we reached the pinnacle of our species. Personally I think we haven't seen even the beginning of it.

Originally Posted by Yarin

When unwound, all reason will eventually fall on to "philosophical propositions", so labelling my argument as such is not sufficient reason to dismiss it.

Let's avoid unwinding too much then.

Originally Posted by megafiddle

But isn't that a matter of degree, not of principle?

It's definitely a matter of principle where grade pays a role. If there is no reason to construct a Thought Experiment because the formulation is so simple it can be understood by mere reasoning, a Thought Experiment is just redundant and pedantic.

Originally Posted by megafiddle

Some thought experiments are just imagined scenarios based on accepted fact or theories. The "twin paradox" was not intended as a proof of time dilation.
It only demonstrates the difference between inertial and noninertial effects.
Is this what you are referring to, or would you say that it also applies to an "experiment" where one or more facts are the basis, and a separate result is being derived?

It applies to Science as a whole. A Thought Experiment, when used as a means to construct a new theory, as was the case with Special Relativity (not entirely accurate, but lets leave it that way), does not constitute proof of any kind. Thought Experiments are not a scientific device. I really can't stress this any further. Special Relativity has its own experimental basis. This is the true device of science and the one that validated SR as a theory.

So a bouncing photon clock thought experiment that tries to demonstrate the possibility of time dilation, as simple as it may sound, cannot evolve from that formulation without being experimentally sound. It's at that point that it can constitute a true scientific theory. In isolation, without any application of the scientific method, the thought experiment is simply a play in logic -- and some simple mathematics -- that don't have the power to evolve. It remains logically speculative.

Originally Posted by megafiddle

No, I wish I had one. But I will use the "bouncing photon clock" just to illustrate what I mean by "a thought experiment that is so simple".

The "experiment" is based on just three quantities, length, time, and velocity. Also it is based on just two scientific facts or principles, motion is relative,
and the velocity of light is constant for all observers.

It just seems that the following must be true:

The photon in the moving clock must travel a longer path between clock "ticks".
The photon must travel at the same velocity in the travelling clock as it does in the stationary (reference frame) clock.
Time = Distance / Velocity; therefore if distance increases, then time increases (time has slowed).

I would imagine though, that another thought experiment could just as well be a valid refutation, if one exists.

I say that the confusion is on the "experiment". We usually make an experiment because we want to observe something. If it is a thought experiment there is no observation, just imagination. So a thought experiment is more like a "thought exercise". Or it is jut a logical conclusion of a theorem as your example seems.

But without being too picky on the words, I would just say that a thought experiment is not a valid scientific experiment as anyway not all experiments are valid scientific experiments.

String Theory -> A reasonable argument with no experimental proofs; hence why it is not currently accepted as Scientific fact.