If everyone would leave as much distance as required by law (2 seconds in most countries), there would be much fewer accidents because... all the highways would be clogged up to almost a standstill during most of the day. They barely even have enough capacity to handle traffic with around one second between cars, let alone two.
Many people seem to think that it's great to have a car stop automatically (stopping is always safe, right?) and that people who think otherwise are just mad control freaks. I beg to differ. What could possibly go wrong?
- You are in the right hand lane, a car pulls up in front of you way too close for you to stop for it, you know there's a gap coming up in the faster left hand lane and you'll be able to smoothly move into it before you reach the stopped car. Only your car has decided to perform an emergency stop for you so you can't even change into the faster lane anymore. Kaboom.
- You are overtaking a car, misjudged the speed of an opposite direction car (or it just drove onto the road), you'll only just make it except... your car has decided to brake for you. Kaboom, no way to avoid the collision.
- You are crossing a street, your car decides to stop because it measured some irrelevant obstacle as being too close, traffic on the street hits you on the side.
- etc, etc, etc...
I have had countless occasions on the road where I intentionally did not brake because there was a much safer alternative to avoid an obstacle, and I would hate to have a car slamming on the brakes for me on every one of those.
You just can't compare this kind of "feature" to any other safety devices like ABS, seat belts, etc... which are rarely ever counterproductive.
I recently took a skidding course, which had a prevention side attached to it as well, and they showed us many examples of crashes where stopping was exactly the wrong thing to do.
I suppose you're right. I was actually going to say you were wrong, but came to my senses while I was writing why:-)
In itself, communicating with someone in the past would not have to violate causality as long as this person could not affect *your* past. If you send a message to someone now, he received it last week (many light years away), sent back the reply last week, and you receive it now (shortly after you sent the original message), causality is not affected. Even better, if you start moving towards or away from him at a sufficiently high speed, he will suddenly be in the future anyway. Big deal, so I thought.
But then I figured it would be trivial to set up more than one connection, with different time differences, send a question with one link and have the reply sent via another link...
So yes, you are right:-)
Isn't there a way to tell whether a photon qubit is still coherent or not? That might allow communication.
For example, in an experiment where single photons (one at a time) were sent out that could go through either one of two openings, an interference pattern emerged suggesting that the photons actually went through both openings simultaneously (in different parallel universes, possibly). If a detector was added to figure out which opening the photons had taken, the interference pattern disappeared.
If you can invent some kind of similar or different experiment that will give a different result for polarized and mixed state photons (for example, if I'm not making some fundamental mistake, the same setup with two openings but each opening equipped with a polarization filter), the ISS can act as the detector. Use a trickle of entangled photons while the ISS is or is not measuring the photons, and check whether an interference pattern comes out. If yes, they just transmitted (or are about to transmit?) a one. Otherwise, it's a zero.
Although on second thought, this entire setup will probably count as a measurement for the quantum gods, they can't possibly be that easily fooled:-)
By the way, I don't know anything about quantum mechanics other than what I picked up here and there...
This would be OK if we were talking about real rapists or other dangerous sex offenders (like people who actually used the internet to meet victims), but for example a mother breastfeeding her child in public and being arrested for it by some overzealous idiot of a police officer is now also going to lose her right to have an internet connection.
There are lots and lots of "sex offenders" that really did nothing wrong, or did something totally unrelated to actual sex. 15-17 couples, people urinating outside, streaking,... It's bad enough already that these people are barred from many jobs (teaching, for example), but now they are even going to be kicked off the internet? What's next? They shouldn't be allowed to visit libraries anymore? Stay 1 mile away from any playgrounds or sports facilities visited by minors?
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If everyone would leave as much distance as required by law (2 seconds in most countries), there would be much fewer accidents because... all the highways would be clogged up to almost a standstill during most of the day. They barely even have enough capacity to handle traffic with around one second between cars, let alone two.
Many people seem to think that it's great to have a car stop automatically (stopping is always safe, right?) and that people who think otherwise are just mad control freaks. I beg to differ. What could possibly go wrong?
- You are in the right hand lane, a car pulls up in front of you way too close for you to stop for it, you know there's a gap coming up in the faster left hand lane and you'll be able to smoothly move into it before you reach the stopped car. Only your car has decided to perform an emergency stop for you so you can't even change into the faster lane anymore. Kaboom.
- You are overtaking a car, misjudged the speed of an opposite direction car (or it just drove onto the road), you'll only just make it except... your car has decided to brake for you. Kaboom, no way to avoid the collision.
- You are crossing a street, your car decides to stop because it measured some irrelevant obstacle as being too close, traffic on the street hits you on the side.
- etc, etc, etc...
I have had countless occasions on the road where I intentionally did not brake because there was a much safer alternative to avoid an obstacle, and I would hate to have a car slamming on the brakes for me on every one of those. You just can't compare this kind of "feature" to any other safety devices like ABS, seat belts, etc... which are rarely ever counterproductive.
I recently took a skidding course, which had a prevention side attached to it as well, and they showed us many examples of crashes where stopping was exactly the wrong thing to do.
Or even better, the system will automatically reboot in 30 seconds, unless you manage to rush to the console quickly enough. Good luck, Dave...
I suppose you're right. I was actually going to say you were wrong, but came to my senses while I was writing why :-)
In itself, communicating with someone in the past would not have to violate causality as long as this person could not affect *your* past. If you send a message to someone now, he received it last week (many light years away), sent back the reply last week, and you receive it now (shortly after you sent the original message), causality is not affected. Even better, if you start moving towards or away from him at a sufficiently high speed, he will suddenly be in the future anyway. Big deal, so I thought.
But then I figured it would be trivial to set up more than one connection, with different time differences, send a question with one link and have the reply sent via another link...
So yes, you are right :-)
So this does allow faster than light communication, right? If Bob modulates his angle, Alice will be able to tell.
Isn't there a way to tell whether a photon qubit is still coherent or not? That might allow communication. For example, in an experiment where single photons (one at a time) were sent out that could go through either one of two openings, an interference pattern emerged suggesting that the photons actually went through both openings simultaneously (in different parallel universes, possibly). If a detector was added to figure out which opening the photons had taken, the interference pattern disappeared. If you can invent some kind of similar or different experiment that will give a different result for polarized and mixed state photons (for example, if I'm not making some fundamental mistake, the same setup with two openings but each opening equipped with a polarization filter), the ISS can act as the detector. Use a trickle of entangled photons while the ISS is or is not measuring the photons, and check whether an interference pattern comes out. If yes, they just transmitted (or are about to transmit?) a one. Otherwise, it's a zero. Although on second thought, this entire setup will probably count as a measurement for the quantum gods, they can't possibly be that easily fooled :-)
By the way, I don't know anything about quantum mechanics other than what I picked up here and there...
This would be OK if we were talking about real rapists or other dangerous sex offenders (like people who actually used the internet to meet victims), but for example a mother breastfeeding her child in public and being arrested for it by some overzealous idiot of a police officer is now also going to lose her right to have an internet connection. There are lots and lots of "sex offenders" that really did nothing wrong, or did something totally unrelated to actual sex. 15-17 couples, people urinating outside, streaking,... It's bad enough already that these people are barred from many jobs (teaching, for example), but now they are even going to be kicked off the internet? What's next? They shouldn't be allowed to visit libraries anymore? Stay 1 mile away from any playgrounds or sports facilities visited by minors?