No. If X then Y is equivalent to "X implies Y" in logic. Either X or Y adds the restriction that not X implies not Y. The common math phrase is "if and only if".
This, on the other hand, is not true. Plenty of things have no physical reality: like abstract concepts. There is no physical quantity of "good" or "evil", for example. There's not even a physical quantity of "red" (not counting the unrelated color charge from QED). There are physical properties that make things red, but "redness" is not by itself physical.
One class of things that is not physically real is probability distributions. They describe information we possess about a real quantities, but the distribution itself is not real. They're common in statistical mechanics as well.
If a quantum wavefunction is purely a statistical tool, then quantum states that are unconnected across space and time are able to communicate with each other.
Actually, what they've proven is that either the wavefunction is a real object and not a statistical tool or quantum states that are unconnected across space and time are able to communicate with each other.
This is fairly similar to, though not the same as, Bell's Theorem.
The rest is speculation.
The paper is actually quite clear on their claims. The speculation was added by others, but is a reasonable interpretation.
What's definitely speculation is your comment, which seems to have no real basis in quantum mechanics:
IMO one observer's wavefunction is the other observer's statistical tool
It doesn't, it only appears to. Special relativity only requires that information (also mass, energy, etc.) can't travel faster than light. Quantum spooky-action-at-a-distance doesn't move any of those things, so the fact that it appears to happen instantaneously over arbitrarily large distances isn't a problem -- it doesn't violate relativity or causality.
You can buy the hexagonal medical ones quite cheaply, but you'd need to get someone to read it for you. However, they're probably not sensitive enough. You'd also need to control for factors like going outside, which can cause a detectable amount of exposure on a good dosimeter.
Both flying and Compton backscatter scanners are well, well below acute exposure rates. The only concern is ionization causing DNA damage (which could lead to cancer). That effect is linear in total exposure. So, just looking at total exposure is, in this case, correct.
To be fair, it worked for the majority of the fish in the supermarket, which are sold under "marketing names" that are unrelated to the fish's original name and may just happen to be the same as the name of a different fish.
That's only true if the fracking is triggering an earthquake that is powered by already-built-up stress. This is actually asking whether fracking is causing additional stress that eventually leads to earthquakes. Adding stress does not, in fact, make earthquakes less serious.
Yes: something they don't point out is that you can't safely choose the words yourself. Your "random" choice of words is not uniformly distributed. You need the computer to give you a password of four words and not let you keep generating new passwords until you get one you like.
They get whether or not the three individuals sent direct messages to one another and what IP addresses they used. They get no content of any messages and they get no information about anyone other than the three named individuals.
I just told you what that was. If you have N possible values for your hash (N=2^256), you need, on average, sqrt(N) = 2^128 objects for there to be a reasonable probability of a collision between some pair of objects. That's the solution to the birthday paradox (for large N).
You'll note that the file or block size doesn't actually show up in that calculation, only the hash size, because the size of the object turns out to be irrelevant. You are just as likely to have hash collisions with 4 MB blocks as you are with 100 MB files. Technically you can store 25 times as many 4 MB blocks as you can 100 MB files, but you can only ever generate or store so very few of them compared to the number you need (2^128) that it doesn't matter.
2^(100*1024*1024*8-256) theoretical collisions per hash. But it's not relevant, because the number of 100 MB files is enormous: 2^(100*1024*1024*8). For any two actually-existing 100 MB files, the likelihood they have the same hash is 1 in 2^256. That's unfairly optimistic, though. You need to consider how big a pool of N files you would need before it was likely that there exists one hash collision within your pool of files. That is N = 2^128.
So in order to have a reasonable chance of collision, you'd need 2^128 100-MB files. That's a problem, though, because there are only about 10^80 ~= 2^240 atoms in the universe.
Dropbox doesn't actually hash whole files, it hashes 4-MB blocks. But it doesn't really matter. You can't even store a reasonable fraction of all 33-byte files, nor do you have enough computational time to ever compute an appreciable fraction of the possible SHA-256 hashes that could, in theory, exist.
It only has any effect if you're watching television or listening to the radio. By the time people knew what was going on, enough to make an emergency broadcast, every TV and radio station had already announced it voluntarily.
The emergency-alert system is actually pretty effective for local serious-weather alerts. (Not the minor weather alerts put together by the TV station itself, but the occasional Icy Roads of Death warning.)
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No. If X then Y is equivalent to "X implies Y" in logic. Either X or Y adds the restriction that not X implies not Y. The common math phrase is "if and only if".
An instance of considering an abstract concept -- which is what the collection of molecule is -- and the concept itself are different.
It's like people on Slashdot don't even know basic philosophy. I suppose that would explain why so many people thought The Matrix was interesting.
FICA is included in that.
Nothing unreal exists
That's an uninteresting tautology.
Everything is physically real.
This, on the other hand, is not true. Plenty of things have no physical reality: like abstract concepts. There is no physical quantity of "good" or "evil", for example. There's not even a physical quantity of "red" (not counting the unrelated color charge from QED). There are physical properties that make things red, but "redness" is not by itself physical.
One class of things that is not physically real is probability distributions. They describe information we possess about a real quantities, but the distribution itself is not real. They're common in statistical mechanics as well.
Did they cover reading the paper instead of a media summary? Because it's a pretty important skill in science.
If a quantum wavefunction is purely a statistical tool, then quantum states that are unconnected across space and time are able to communicate with each other.
Actually, what they've proven is that either the wavefunction is a real object and not a statistical tool or quantum states that are unconnected across space and time are able to communicate with each other.
This is fairly similar to, though not the same as, Bell's Theorem.
The rest is speculation.
The paper is actually quite clear on their claims. The speculation was added by others, but is a reasonable interpretation.
What's definitely speculation is your comment, which seems to have no real basis in quantum mechanics:
IMO one observer's wavefunction is the other observer's statistical tool
It's not ridiculous at all, it's just counterintuitive. But then, intuition about such things is difficult at best.
It doesn't, it only appears to. Special relativity only requires that information (also mass, energy, etc.) can't travel faster than light. Quantum spooky-action-at-a-distance doesn't move any of those things, so the fact that it appears to happen instantaneously over arbitrarily large distances isn't a problem -- it doesn't violate relativity or causality.
Or you synchronize clocks halfway between the two points and move both clocks at roughly equal speeds.
No.
Nobody even knows how many foreign bases the USA has
I'm certain there are people in the US government who know how many foreign bases the US has.
No, it's around 27% -- including all levels of government -- not 50%.
Also, if you're including state and local taxes, then the taxing organization is not "the US government".
You can buy the hexagonal medical ones quite cheaply, but you'd need to get someone to read it for you. However, they're probably not sensitive enough. You'd also need to control for factors like going outside, which can cause a detectable amount of exposure on a good dosimeter.
Both flying and Compton backscatter scanners are well, well below acute exposure rates. The only concern is ionization causing DNA damage (which could lead to cancer). That effect is linear in total exposure. So, just looking at total exposure is, in this case, correct.
Seems unlikely. Humans are, historically, much more successful at controlling domesticated animals than at controlling humans.
To be fair, it worked for the majority of the fish in the supermarket, which are sold under "marketing names" that are unrelated to the fish's original name and may just happen to be the same as the name of a different fish.
That's only true if the fracking is triggering an earthquake that is powered by already-built-up stress. This is actually asking whether fracking is causing additional stress that eventually leads to earthquakes. Adding stress does not, in fact, make earthquakes less serious.
Yes: something they don't point out is that you can't safely choose the words yourself. Your "random" choice of words is not uniformly distributed. You need the computer to give you a password of four words and not let you keep generating new passwords until you get one you like.
That's good, I need some lunch.
My post does only address what is covered by this case -- not what the investigators could possibly request (and successfully obtain) in the future.
No.
They get whether or not the three individuals sent direct messages to one another and what IP addresses they used. They get no content of any messages and they get no information about anyone other than the three named individuals.
15 happens to be an unfairly easy number to factor with a quantum computer.
Factoring 100 using Shor's algorithm really requires closer to 70 qbits.
Those are different taxes, you know. Police, schools, and road maintenance are state and local taxes. Everything you complained about is federal.
I just told you what that was. If you have N possible values for your hash (N=2^256), you need, on average, sqrt(N) = 2^128 objects for there to be a reasonable probability of a collision between some pair of objects. That's the solution to the birthday paradox (for large N).
You'll note that the file or block size doesn't actually show up in that calculation, only the hash size, because the size of the object turns out to be irrelevant. You are just as likely to have hash collisions with 4 MB blocks as you are with 100 MB files. Technically you can store 25 times as many 4 MB blocks as you can 100 MB files, but you can only ever generate or store so very few of them compared to the number you need (2^128) that it doesn't matter.
2^(100*1024*1024*8-256) theoretical collisions per hash. But it's not relevant, because the number of 100 MB files is enormous: 2^(100*1024*1024*8). For any two actually-existing 100 MB files, the likelihood they have the same hash is 1 in 2^256. That's unfairly optimistic, though. You need to consider how big a pool of N files you would need before it was likely that there exists one hash collision within your pool of files. That is N = 2^128.
So in order to have a reasonable chance of collision, you'd need 2^128 100-MB files. That's a problem, though, because there are only about 10^80 ~= 2^240 atoms in the universe.
Dropbox doesn't actually hash whole files, it hashes 4-MB blocks. But it doesn't really matter. You can't even store a reasonable fraction of all 33-byte files, nor do you have enough computational time to ever compute an appreciable fraction of the possible SHA-256 hashes that could, in theory, exist.
It only has any effect if you're watching television or listening to the radio. By the time people knew what was going on, enough to make an emergency broadcast, every TV and radio station had already announced it voluntarily.
The emergency-alert system is actually pretty effective for local serious-weather alerts. (Not the minor weather alerts put together by the TV station itself, but the occasional Icy Roads of Death warning.)