this post was submitted on 19 Feb 2026
97 points (96.2% liked)
Technology
81534 readers
4404 users here now
This is a most excellent place for technology news and articles.
Our Rules
- Follow the lemmy.world rules.
- Only tech related news or articles.
- Be excellent to each other!
- Mod approved content bots can post up to 10 articles per day.
- Threads asking for personal tech support may be deleted.
- Politics threads may be removed.
- No memes allowed as posts, OK to post as comments.
- Only approved bots from the list below, this includes using AI responses and summaries. To ask if your bot can be added please contact a mod.
- Check for duplicates before posting, duplicates may be removed
- Accounts 7 days and younger will have their posts automatically removed.
Approved Bots
founded 2 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
No, not if the observer can see the message arrive first, and immediately send a faster than light signal to the sender that turns off their transmitter, preventing the sending of their message.
If they see the message arrive, it has already been sent (and received). Not seeing it get sent yet doesn't mean it hasn't happened yet. You're not accounting for the frame of reference translation involved. Some of the information in your example has travel time. None of that information starts traveling before the things that created that information occurred, though. Even if it might look like that from some perspectives. It won't look like that to others.
I'm sorry, but all of special relativity disagrees with you.
The only way that an observer can see a message arrive first before it was sent is if that message was also faster than light.
The propagation of the information that the signal was sent will be travelling before the information of the result starts to propagate. So even if the message is sent equal to light speed, there's only one point on the two expanding spheres where the cause and effect appear simultaneously. That message you're observing would have to move quicker than light for any observer to be overlapped by the effect bubble before the cause bubble reaches them. Both of those bubbles expand at the same rate.
How are you beating an ftl signal with your own ftl signal if you're relying on information that is moving at light speed to react to?