Ask Science

8641 readers

25 users here now

Ask a science question, get a science answer.

Community Rules

Rule 1: Be respectful and inclusive.

Treat others with respect, and maintain a positive atmosphere.

Rule 2: No harassment, hate speech, bigotry, or trolling.

Avoid any form of harassment, hate speech, bigotry, or offensive behavior.

Rule 3: Engage in constructive discussions.

Contribute to meaningful and constructive discussions that enhance scientific understanding.

Rule 4: No AI-generated answers.

Strictly prohibit the use of AI-generated answers. Providing answers generated by AI systems is not allowed and may result in a ban.

Rule 5: Follow guidelines and moderators' instructions.

Adhere to community guidelines and comply with instructions given by moderators.

Rule 6: Use appropriate language and tone.

Communicate using suitable language and maintain a professional and respectful tone.

Rule 7: Report violations.

Report any violations of the community rules to the moderators for appropriate action.

Rule 8: Foster a continuous learning environment.

Encourage a continuous learning environment where members can share knowledge and engage in scientific discussions.

Rule 9: Source required for answers.

Provide credible sources for answers. Failure to include a source may result in the removal of the answer to ensure information reliability.

By adhering to these rules, we create a welcoming and informative environment where science-related questions receive accurate and credible answers. Thank you for your cooperation in making the Ask Science community a valuable resource for scientific knowledge.

We retain the discretion to modify the rules as we deem necessary.

founded 1 year ago

MODERATORS

sabbah@lemmy.world

AradFort@lemmy.world

ken_cleanairsystems@lemmy.sdf.org

count_of_monte_carlo@lemmy.world

Does faster than light travel violate causality? Why/Why not? How? (discuss.tchncs.de)

submitted 1 year ago by surepancakes@discuss.tchncs.de to c/askscience@lemmy.world

2 comments fedilink hide all child comments

I have heard this mentioned several times with this exact wording, that faster than light travel would break/violate causality and I do not exactly understand why and how it would do that. Could someone more well-versed in physics explain to me why that would be the case? Or is it not the case? (Yes, I am fully aware, that faster than light speeds are impossible in real life, but I am more curios about how it would hypothetically affect physics, were it possible). I am somewhat familiar with physics and more so with mathematics (engineering student), if that helps anyone to explain it at an appropriate level.

top 2 comments

sorted by: hot top controversial new old

[–] ExchangeInteraction@lemmy.world 1 points 1 year ago (1 children)

This argument, as far as I know, relies on the nature of time dilation. You see as your velocity increases closer and closer to the speed of light, time itself begins to slow down. This is not an analogy or some fancy math trick, this is a real thing you can measure in the lab. As you get closer and closer to the speed of light time slows more and more. Such that as you reach the speed of light (again this is physically impossible at least for anything with mass) you can think of time as stopping. So for light or anything that moves at the speed of light they're kind of isn't such a thing as time, but I digress.

So (again even though it's actually impossible), what happens as you start to go faster than light? Does this trend continue? If it does that would mean that time starts to reverse. And once you see that faster than light travel might imply time reversal, it should be easier to understand how this would violate causality. Because how do you get event A caused by event B when event B was before even A?

[–] surepancakes@discuss.tchncs.de 1 points 1 year ago

Thank you for your answer. When viewed from this perspective it makes more sense.