Intriguing thought experiment

In summary, the conversation discusses the hypothetical scenario of a car traveling at the speed of light and whether the stereo would work. The two theories presented are that the speakers would work fine relative to the passengers due to the unchanging system within the cabin, but the particles in the car moving faster than the speed of light may cause the sound waves to not propagate properly. Ultimately, it is concluded that the stereo would still work as everything within the car would function normally, despite its high velocity.
  • #1
Hello all! I was not sure were to post this, but I was asked a very interesting thought experiment on Facebook today and was wondering if I could get everyone's opinions on it.

Ok, so suppose we could really annoy Einstein and manage to get a car to go the speed of light. The question is, would the stereo speaker's work?

Now I have two different theories. One, assuming the system within the cabin is unchanging, then the principals of reference frames would dictate that the speakers would work fine relative to you.

But all of the particles in the car are going faster than the speed of light, so if a sound wave was emitted, would you not move faster than it could propagate? And if that happens, would you be able to hear anything at all?

Just thought I'd share this little bit of intrigue with you all.
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  • #2
We get this a lot.
Ransom7D said:
...suppose we could really annoy Einstein and manage to get a car to go the speed of light. The question is...

Q: If we could ignore the laws of physics what would happen to the laws of physics?

A: Fairies and unicorns would jump out of your pants.
Seriously, it cannot happen which is why asking what "would" happen makes no sense.

The question you want to ask is properly phrased this way:

Q: If we had a car that could accelerate at a constant rate without limit, so that it approached arbitrarily close to the speed of light (say, 99.9999999999%), would the car's stereo work?

A: Yes. Everything within the car would go on exactly as it had before, no matter how long you accelerated. The only way you would have any idea you were moving fast relative to something else in the universe is to look out the window.

Why? Two phrases to look up: Time dilation. Velocity addition.
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What is an intriguing thought experiment?

An intriguing thought experiment is a mental exercise that poses a hypothetical situation or scenario in order to explore a concept or idea. It often challenges our assumptions and encourages us to think critically about a particular topic.

Why are thought experiments important in science?

Thought experiments are important in science because they allow scientists to test theories and explore possibilities without the need for expensive equipment or real-world experiments. They also help to stimulate creativity and push the boundaries of our understanding.

What makes a thought experiment "intriguing"?

A thought experiment is considered intriguing when it presents a scenario that is difficult to imagine or goes against our common sense. It should also challenge our beliefs and encourage us to think in new and unconventional ways.

Can thought experiments provide concrete evidence or proof?

No, thought experiments cannot provide concrete evidence or proof. They are meant to stimulate thinking and generate ideas, but they do not provide empirical evidence. They can, however, lead to new hypotheses that can be tested through real-world experiments.

Are there any famous examples of intriguing thought experiments?

Yes, there are many famous thought experiments in science, such as Schrödinger's cat, the trolley problem, and the twin paradox. These experiments have helped scientists to better understand complex concepts in physics, ethics, and philosophy.

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