1,279 karma · joined August 15, 2011
It definitively answers the question of when wave collapse occurs and what causes it.
The answer given by the Everett Interpretation is simply that there is no wave collapse, and what we observe is the result of our brains being in a superposition of multiple states.
That's not the Copenhagen Interpretation. Interpretations that claim this are called "Objective-collapse" theories. Back when I cared a lot about this, the most popular Objective-collapse theory was GRW:
The Everett Interpretation is clearly the simplest theory because the deep mystery of what would cause probability waves to collapse is made completely irrelevant. There is no wave collapse to worry about or to explain.
I mean it builds the term "measurement", which is an undefined and unscientific concept, right into the laws of physics. Personally, I find this to be virtually nonsensical.
This assertion does not make sense to me. The Everett Interpretation and the Bohm Interpretation are experimentally indistinguishable from each other, as I understand things. Consequently, there is no mystery at all with the Everett Interpretation as to why things appear to us the way that they do.
Since the Everett Interpretation is a significantly simpler theory than Bohm's, we should prefer it due to Occam's Razor. On the other hand, since they are experimentally indistinguishable from each other, we can never scientifically assert which of the two is correct, no matter how much evidence we have.
As I understand things, most physicists don't give much thought to which interpretation is correct, since any experiments to distinguish between the various interpretations are virtually impossible to do. And most physicists don't care about distinctions for which there will be no experimental evidence.
Among the physicists who do care about the different QM interpretations, it is my understanding that most would go with the Everett (AKA "Many Worlds) Interpretation these days. All other interpretations that I know of are hugely problematic, but there are no significant problems at all with the Everett Interpretation. The only problem is that many people consider it to be "creepy". But not liking the best theory because it is "creepy" isn't very good science, if you ask me.
Regarding there being no single-world interpretation that is logically self-consistent, I'm not convinced about this: The Bohm Interpretation, for instance, is experimentally indistinguishable from the Everett Interpretation. I.e., no matter what incredible technology and powers of QM experimentation we might develop in the future, we will never be able to do an experiment, even in theory, that tells us which of these interpretations is the right one.
Consequently, it would seem that the Bohm Interpretation is logically self-consistent. The problem with the Bohm Interpretation is that it's very ad hoc and violates Occam's Razor. It only exists in order to calm our feelings about the universe being "creepy".
On the other hand, it's certainly been proven that this cannot be used to transmit information that you might like to at faster than the speed of light. So causality is preserved in any case.
It would be very interesting to know how Einstein would have received the Everett Interpretation.
This is what Einstein had to say about Bohm's Interpretation, in a letter that Einstein wrote to Bohm about six months before he died:
"In the last few years several attempts have been made to complete quantum theory as you have also attempted. But it seems to me that we are still quite remote from a satisfactory solution to the problem. I myself have tried to approach this by generalising the law of gravitation. But I must confess that I was not able to find a way to explain the atomistic character of nature. My opinion is that if an objective description through the field as an elementary concept is not possible, than one has to find a possibility to avoid the continuum (together with space and time) altogether. But I have not the slightest idea what kind of elementary concepts could be used in such a theory."
From my reading of this, it seems that Einstein's greatest concern here is that GR and QM had not yet been unified.
There is a sense in which no competent scientist can fully accept either QM or GR, despite their incredible accuracy in making predictions, because we know that they are incompatible with each other, and consequently, both wrong or incomplete in some very important manner.
But didn't Einstein write the following in his own book?
“I believe in intuition and inspiration. … At times I feel certain I am right while not knowing the reason. When the eclipse of 1919 confirmed my intuition, I was not in the least surprised. In fact I would have been astonished that it turned out otherwise. Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution. It is, strictly speaking, a real factor in scientific research.”
Wait? Since when did Einstein not accept Quantum Mechanics? He won the Nobel Prize for his work in discovering an important part of Quantum Mechanics.
Einstein rejected the Copenhagen Interpretation of Quantum Mechanics. That's not the same thing as rejecting Quantum Mechanics.
I've seen no claims that he would object to either the Everett or Bohm Interpretations of QM. (But then again, he died before they were invented.)
Einstein, by the way, is far from the only critic of the Copenhagen Interpretation. Quite a few physicists are drawn to the Everett Interpretation instead, for instance.
One is the "Many Worlds" interpretation. (AKA, the Everett interpretation.) In this QM wave functions never collapse, and the only reason that we perceive there to be probability distributions is that the lack of collapse results in many different apparent worlds. Though in reality, there is really just one very big complicated world, but the difference parts of it stop effecting each other via a property called "decoherence".
Another deterministic interpretation is the Bohm interpretation, in which the particles are push around by a "pilot wave", which is the same wave function that never collapses in the Many Worlds interpretation. Since the "pilot waves" never collapse in the Bohm interpretation, one might wonder, then why you don't also end up with many worlds here too, but it is taken that the reality that we perceive is always determined by the particles that are being pushed around by the pilot waves.
One point of interest is that the Many Worlds interpretation and the Bohm interpretation are experimentally indistinguishable from each other.
Regarding the postulation of a multiverse, this is almost certainly true, if you ask me. It would seem to be the only way to explain the apparent "fine tuning" of the universe. Unless you believe that it was tuned by God, that is. But if that's the case, I have a few nits to pick with some of the choices that he or she made.
We have no reason to believe that P = NP, but on the other hand, without proof, we can't know for certain that it doesn't. We're not infinitely smart, and we just might not have yet seen the way in which P does equal NP.
Surely we live in a world filled with uncertainty, and we have to be able to deal with that. But in instances in which we can be certain about certain things, it certainly benefits us.
Also, I don't understand the argument that learning to think with the rigor of mathematics is somehow detrimental. There are many different ways of reasoning, and a well-educated person should strive to learn a good amount of these useful mental tools. Learning to think with mathematical rigor is a good tool to have in one's mental toolbox.
IME many computer programmers learned Lisp in college and for some reason hated it–I think in part due to the syntax and in part because they had a hard time with recursion and other "mind-bending" concepts. They often still harbor an irrational precedent to this day.
Me, on the other hand, I loved Lisp as soon as I learned it. (Perhaps I was primed by having learned APL in high school.) I changed my major from Astrophysics to Computer Science because I felt that SICP was even cooler than black holes and neutron stars.
If JavaScript had had Lisp syntax, then everyone would still be using Flash. Or some other plugin that provided a language with a more popular syntax.
That's an amusing idea. But it's extremely unlikely for the same reason that you are unlikely to see C++ rewritten in JavaScript.
It's possible, however, that over time, more and more languages might target JavaScript, rather than the JVM or the native hardware.
For instance, I program in Scala for a living. The main platform for Scala is the JVM, but there's also Scala.js, which targets JavaScript. And in fact, we now write most of our "JavaScript" in Scala, rather than in JavaScript.
I suppose that someday there might be a version of Java that targets JavaScript, and then your dream might come true. Oh wait... it already happened! It's called GWT and it's been around for a decade.
For purchasing online, most people just immediately type "amazon" into their web browser. People will never have any reason to do anything differently, unless Amazon starts screwing up the user experience, or becomes significantly more expensive than other online sites. Neither of those things is likely to happen.
Suggesting that such things will happen is like suggesting that some other search engine is going to quickly replace Google.
I guess all bets are off when one tries to look ten years out–the entire world can change radically in ten years–but personally, I'd bet good money that Amazon and Google will still be the largest players by far for their markets.
The more interesting question, I think, is for how long will Amazon maintain its lead in cloud computing. Cloud computing is something of a commodity, so companies will have a great deal of incentive to go with whoever can do it most cheaply. As long as they do it well, that is. I'd still put my money on Amazon.
I also loved the hell out of my MacBook Air. I recently gave that to my girlfriend. (Hence me now having a MacBook Retina.) It's four years old and still works as well as the day I got it. It's perfectly zippy. It's only downsides are that the screen isn't nearly as good as the MacBook Retina screen, and the speakers don't go loud enough.
Re iMac fans: well, I love the fact that my MacBook Retina makes no noise at all. But the noises made by my work and home iMacs are not loud enough to bother me in any way. They certainly handle their loads just fine, as long as you don't mind a bit of extra white noise.
But then again, I kind of miss the days when you could hear the disk drive in a computer chugging away. You could often tell what the computer was working on by the rhythm of the chugging.
Well, they're not that loud. The building H/V airflow is usually a lot louder. And my Retina MacBook doesn't even have a fan. (Though I also don't do a lot of software development on it, I have done development on slower machines, and it wasn't terribly painful. Depending on what I was doing, of course.)
I still remember the days of programming in C++ using C-front, and a compile would take 20 minutes. Being a gdb wizard was essential. These days, even with Scala, compilation is fast enough on a four-core iMac that debugging via print statements is easier than using a debugger.
I guess I'm old enough that I just haven't gotten spoiled by expecting everything to be superfast. Though what does annoy me is how slow many websites are. Grrrrrr! When programming in fancy IDEs is faster than surfing the web, you know that something is wrong with the world....
I love them all to death. It doesn't really matter to me whether I could have gotten something cheaper. If I did that, I'd have a little bit more money, and I'd be significantly less happy.
The book was very interesting. I'm not sure that I agree with his conclusion, however, which was (1) Yes, you die. (2) So what?
(I.e., there being someone else who is just like you is just as good as not dying.)
From my point of view, if the result is just as good as not dying, then that's what I meant by not dying. But I'm sure I'd have to write just as much as Parfit did to make that claim credible to philosophers.
When you were done, you'd leave through the door, which would lock behind you, and then for a minute or two, it would go through a self-cleaning cycle, making itself (putatively) spotless for the next customer.
They even had the same idea scaled up to entire motels. Near Lyon, I needed to catch 3 hours of zzz's before going to the airport. I found a motel called "Formule 1". It was a seemingly automated motel. You hardly ever saw an employee.
To park your car, you slid your credit card through a card reader at the parking lot gate, and it charged you $20 or so. You would be given a receipt with a combination number for the front door and for your room.
The bathrooms were down the hall from your room. They were somewhat similar to the fancy porto-poties. Though they also had showers in them. The shower was on a timer. When you left the bathroom, the door would lock behind you for a while, as it would go through its cleaning cycle.
France is strange!
I'm not sure you have a conception of how truly BIG the universe is. In fact, according to current cosmological evidence, it is infinitely big.
But even if we confine our discussion to our Hubble Sphere, there is almost certainly life elsewhere in the universe. It's just that that life might be very, very far away.
It's not bad, but I still don't really like scrums.
Advocates for Tor say it supports freedom of expression, including in countries where the Internet is censored, by protecting the privacy and anonymity of users. The mathematical underpinnings of Tor lead it to be characterized as acting "like a piece of infrastructure, and governments naturally fall into paying for infrastructure they want to use".[139]
The project was originally developed on behalf of the U.S. intelligence community and continues to receive U.S. government funding, and has been criticized as "more resembl[ing] a spook project than a tool designed by a culture that values accountability or transparency".[20] As of 2012, 80% of The Tor Project's $2M annual budget came from the United States government, with the U.S. State Department, the Broadcasting Board of Governors, and the National Science Foundation as major contributors,[140] "to aid democracy advocates in authoritarian states".
Philosophers love formal logic, so that's one thing that's of interest.
Once you have a good understanding of logic, Philosophy aims to investigate important questions that other fields don't seem to have a good grasp of. Here are some of them:
- How can that sensation of redness that you experience when you look at a ripe tomato arise from or be explained by scientific law, which seems to only answer questions that are very qualitatively different from this question? And how do you know that your friend has that same sensation of redness? Perhaps when he looks at a ripe tomato, what he experiences is what you experience when you look at a blueberry.
- If Star Trek transporters work by ripping apart all your atoms and then making a copy of you at the other end from atoms at the destination, would that still be you? Or would you have died, and there be a new person who is deluded into thinking he's you.
- When you push around a wrinkle in your bed-spread, is that wrinkle itself a real thing, or is it just similar different bunches of your bed-spread?
- If you could murder one innocent person to save ten people, would that be the right thing to do? If so, why? If not, why not? What if you could save a million people instead?