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Simulated reality and *ism
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Krauss is basing his theory on QFT which is the quantum field. QFT suggests that any physical reality is possible, anything from "nothing" to what we observe as our objective universe.
To quote one of the links you musn't have read:
Quantum field theory is a kind of special-relativistic version of quantum mechanics that does not incorporate general relativity, so it's not surprising to see them invoking the extraneous concept of general relativity to justify their claims - if you really think a person is basing his claims off of X - in our case QFT - & you see some obvious flaw in their assumptions - namely that the QTF vacuum isn't empty in the sense Krauss implied - then you really ought to afford the person you're criticizing a bit more respect and ensure they're not making trivially obvious errors - in this case the error being that Krauss wasn't referring to the QFT vacuum in the first place which could only be because he's invoking more than QFT - so let this be a lesson..."Putting [general relativity and quantum mechanics] together, one can imagine that the universe started in the total empty geometry – absolute nothingness – and then made a quantum tunneling transition to a nonempty state"
http://debunkingwlc.wordpress.com/2010/08/11/alexander-vilenkins-model-of-cosmic-origins/When Krauss says "there's no quantum" he is not being truly honest,
In your rush to slander Krauss as dishonest you missed a section from one of my links that could have stopped you from slandering someone behind their backs:
Here you have the pre-youtube incarnation of Krauss making more or less the same arguments Krauss does, saying that a universe begins in a totally empty geometry [incorporating general relativity "before" quantum mechanics it seems] & only then once it is inside this empty geometry it makes a quantum transition to a non-empty state.As Vilenkin’s colleague Alan Guth explains,
Putting [general relativity and quantum mechanics] together, one can imagine that the universe started in the total empty geometry – absolute nothingness – and then made a quantum tunneling transition to a nonempty state. Calculations show that a universe created this way would typically be subatomic in size, but that is no problem . . . Vilenkin was able to invoke inflation to enlarge the universe to its current size.
The Inflationary Universe (1997), Page 275
http://debunkingwlc.wordpress.com/2010/08/11/alexander-vilenkins-model-of-cosmic-origins/as quantum is the most fundamental theory we know of, and is the basis of his own theory.
I just quote the sentence "Putting [general relativity and quantum mechanics] together" & your claim goes out the window, he simply can't be basing his theories off QFT alone if they're invoking general relativity as a justification for what they're saying:
But to re-iterate the point I've made, Guth has made, Vilenkin has made & Krauss has made - they are incorporating the extraneous idea of gravity to arrive at their theories, even on Q&A which I randomly threw on this morning motivated by this discussion:There is currently no complete quantum theory of the remaining fundamental force, gravity. Many of the proposed theories to describe gravity as a QFT postulate the existence of a graviton particle that mediates the gravitational force. Presumably, the as yet unknown correct quantum field-theoretic treatment of the gravitational field will behave like Einstein's general theory of relativity in the low-energy limit.
https://en.wikipedia.org/wiki/Quantum_field_theory
from 28:30 on for about a minute you have Krauss explaining how it is with the addition of gravity that he can make his claims. So no, quantum theory is not the basis of his theory, I'd be willing to bet money he's made that clear in his book as well, something (giving you the benefit of the doubt, something you clearly won't afford to Krauss) I assume you missed due to confusing Tryon's model with Vilenkins...Everything that is possible in our universe stems from quantum theory,
You know this isn't true, nobody knows if the orbits of the planets is explainable in terms of quantum theory...you cannot state "there's no quantum", except to a non scientific audience.
Again I'll quote one of my links:
Here are other physicists explaining how there is "no quantum", it begins in an "empty geometry" & after this the dreaded quantum (:eek:) kicks in - It's completely irrelevant what they mean by an empty geometry, & it doesn't even matter if the claim makes sense, the important thing for us is that the universe exists in what they mean by nothing & once inside this nothing it makes a quantum transition - this isn't the fields of energy vacuum you referred to earlier in the thread (the only reason I posted). In other words, the claim "no quantum" is accurate.In a nutshell, Vilenkin’s model is a variation on Edward Tryon’s “vacuum fluctuation” model, but instead of the universe appearing within a background of space, the universe appears from an empty geometry (i.e. “nothing”). As Vilenkin’s colleague Alan Guth explains,
Putting [general relativity and quantum mechanics] together, one can imagine that the universe started in the total empty geometry – absolute nothingness – and then made a quantum tunneling transition to a nonempty state. Calculations show that a universe created this way would typically be subatomic in size, but that is no problem . . . Vilenkin was able to invoke inflation to enlarge the universe to its current size.
The Inflationary Universe (1997), Page 275
http://debunkingwlc.wordpress.com/2010/08/11/alexander-vilenkins-model-of-cosmic-origins/Open your mind and start asking the tough questions.
Unfortunately it takes a closed mind to spot how the justification offered by someone extremely quick to slander fails based on the one weak link in their entire argument - you've just called him dishonest for neglecting "the theory of everything that is possible in our universe" when in fact it's precisely because of the fact that his theory merges "the theory of everything that is possible in our universe" with the one exception [you fail to mention] to "the theory of everything that is possible in our universe" (gravity, currently not adequately explained in the context of quantum mechanics) that he can make his claims. In case that was all too much, I literally have Guth saying point blank that it is because they are "Putting [general relativity and quantum mechanics] together" that "one can imagine that the universe started in the total empty geometry". Again, there is none of the quantum vacuum or fields of energy you were referring to, by incorporating extraneous ideas they end up with something new. Even if it's complete nonsense that's irrelevant, the simple point is that this is what they were saying, there's no need to go off pulling out claims of dishonesty...Why is it that in every interview Krauss claims there is no need for a creator due to his theory. Why does he reference Dawkins so much? Why did Dawkins wax so lyrically in the preface to his book, claiming this was the final nail in the theist coffin? Why are Dawkins and Krauss on a world tour arguing against theism?
Hopefully your suspicions of Krauss will dissipate somewhat of their own accord now that you see he was making proper arguments all along and in fact it was you who was misinterpreting things. I'll be on the lookout for your arguments against Dawkins
Should they not be doing science, which is what they are good at?
Why "should" they? Who are we to tell people what they "should" be doing? I wonder do you invoke such authoritarian judgement upon yourself, for instance - "should" you be posting slander against someone before properly reading the links claiming to refute you? Should you be posting on the internet when you could be juggling 10 miniature polar bears, 5 to each hand (1 to each finger) after sufficient practice that you should have begun in utero? Freedom my man, freedom 0 -
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Let me first interpret it as if you were saying: 'it doesnt matter what you thought the probability of the coin toss was, it either came up heads or tails, which didnt have anything to do with your notions of its probability'.
That would be true, of course, taken literally.
No, it is more like this.
You toss a "coin" with n number of sides (could be 2, could be a million). Based on your previous experience with coins you suppose it has two sides, but you don't actually know how many sides it has. Because you suppose it has two sides you conclude that it probably has about a 50/50 chance of landing on side A.
Based on your experience of two sided coins you think this is a reasonable conclusion. But of course since you don't know how many sides there are you can't say that.
When judging how likely something we imagine is we compare it to other things we imagine. But this limits the set of considered outcomes far too much.
You cannot say how likely it is that the universe is a compute simulation because you don't have a clue how large the set of possible outcomes are. You can only say how likely it is based on the other things you imagined it could be. Which is rather irrelevant to how it actually is.I've said this before - but if we construct simulations, in which we simulate other sentient beings (a huge 'if') - would that count as 'discovering evidence that we are in some sort of simulation'?
No, no more than discovering a two sided coin is evidence that the n-sided coin is two sided and the odds of any particular side is 50/50.
The most you can say is that it is possible that the universe is a simulation. But then it was always possible the universe was a simulation (in the same way that the existence of a two sided coins makes it possible that the n-sided coin is two sided).I am sure it would change people's beliefs in practice - if people find out that some guy over there has a universe simulation with sentient beings in it, we are going to start thinking "wait a minute, maybe we're in such a simulation".
That is unfortunately true, but it has no more significance than people saying their favourite TV programme of all time is the one they last enjoyed.
The fact that humans just realised the universe could be X is not evidence that the universe is X, any more than discovering the existence of a 2 sided coin is evidence that the n-sided coin has two sides.
Nor is the fact that we can produce simulations evidence in support of a simulated universe, because we have no grounds to say the rules of this universe effect the rules beyond it it.
Or to put it another way, even if we couldn't simulate universes in this universe that doesn't mean our universe wouldn't be a simulation.
The only "significant" thing happening here is that you realised we could be a simulated universe. But that has no relevance to if we are, or how likely that is.
It is the classic human fallacy of confusing something being significant to you with something being significant in general.Technically, yes, it says nothing for certain about what is actually outside the box.
But surely it alters our subjective probability?
I don't know what you mean by our "subjective probability"?Given the position you are arguing, I don't think you can say 'in all likelihood ...' there, but anyway.
I can because I'm arguing the opposite of what you are arguing.
You are arguing that based on our experience we can narrow down the set of possible causes for the universe. I'm arguing the opposite.
In all likelihood I'm right
Given that you are 'in a box', all that you can imagine is outside, is related to your experience inside.
So, you tend to imagine the outside is more likely to be a box, than a mountain, or anything else you can or can't conceive.
Now, I'm not saying that what is outside the box is more likely to be a box than not be a box.
What I am saying is that it is reasonable to start off by assuming that what is outside is more likely to be similar to what is inside, than it is to be any other single thing.
That's an inductive argument.
The issue with this is that you are applying it to a system you have no experience with. As such inductive reasoning fails.
It is not the inductive reasoning bit that is the issue, it is the applying inductive reasoning to a domain of which you know nothing about the rules of the system.
Think of it this way, you watch a lot of football, and conclude that you cannot touch the ball with your hands in football unless you are the goal keeper.
You then imagine what it must be like to play Rugby, a came you have no experience with, and conclude that the same rule should apply because it is all you are familiar with. You might think that is reasonable, after all all you have experienced is football and that rule holds in football.
Then someone says "Rugby is nothing like football". Given that information is it still sensible to conclude it is likely that Rugby follows the same rule about touching the ball as football?That's a misrepresentation of the argument.
I'm not saying its reasonable to conclude whatever is outside the box is also some box like form.
I'm saying that in the absence of other evidence, surely we should think its more likely to be box-like than another, otherwise equally likely possibility?
Why? We should think we have no idea, just like we should conclude we have no idea what Rugby is like, rather than assuming it is probably like football because football is all we have experienced.
We know from experience that this universe appears to follow rules we are familiar with.
We have zero reason to conclude that anything beyond this universe does.
We are back to being comfortable with "We don't know"All very weak, inductive, argument from very weak evidence; but I don't think that means its useless.
What use does it have?Again, that's like arguing that the people who have seen the previous cointosses mean absolutely nothing to the likelihood of the coin coming up heads next toss.
You haven't seen previous universes. You have no experience with the rules of how one creates a universe.
Induction is only useful in a system that follows rules you are experienced with.
The issue here is not that you are using inductive reasoning, it is that you are using inductive reasoning applied to a system you have no experience of. And more importantly you know you have no experience of it.0 -
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My criticism of Krauss is not with the science, it is his philosophy or rather his ideology. I don't believe I am slandering him as my disagreement is with the ideological conclusions he draws from very speculative science.In my opinion Kraus is a good scientist but a poor philosopher.
See now I mentioned the word slander for a specific reason, not because you were disagreeing with his philosophy - you said he wasn't being fully honest because he wasn't admitting that 'the quantum' was the basis of his own theory when in fact I've given you evidence from his own mouth that there's more to it than quantum mechanics & why he simply can't just be using QFT or QM to say what he says. I mean come on, don't misconstrue the situation: to use your rhetoric - be honest about itIn defense of my earlier remarks, the vast majority of Krauss' book relates to how our observed physical universe emerged from empty space or the quantum vacuum, which I think we agree is anything but "nothing", it consists of fields of energy with virtual particles popping in and out of physical existance.
Just because Frodo & Sam nearly lose the ring plenty of times on their journey to Mordor doesn't mean they don't eventually get to Mount Doom
How in good conscience could you read 8 chapters of his book with him apparently talking about fields of energy & then come across the following paragraph:
then continue reading assuming he was talking about fields of energy? No wonder you think so little of him, if you see him contradicting his whole book with sentences like this (from your pov) then Krauss simply can't be a rational actor, he must be suspect :rolleyes:While inflation demonstrates how empty space endowed with
energy can effectively create everything we see, along with an
unbelievably large and flat universe, it would be disingenuous to
suggest that empty space endowed with energy, which drives
inflation, is really nothing. In this picture one must assume that
space exists and can store energy, and one uses the laws of
physics like general relativity to calculate the consequences. So if
we stopped here , one might be justified in claiming that modern
science is a long way from really addressing how to get something
from nothing. This is just the first step, however. As we expand
our understanding, we will next see that inflation can represent
simply the tip of a cosmic iceberg of nothingness.
(Last paragraph of chapter 9)Vilenkin's "vacuum fluctuation" model is highly speculative and does not seem to have gained much traction in the scientific community since first proposed in the 1980s. Krauss actually does not spend a lot of time on this model in his book.
At the most pivotal point of chapter 10, the chapter that explains the whole point of the book, he says:
Despite the character assassination credibility argument you're trying to employ he seems to pull this traction-less theory up (in a paragraph littered with names like Stephen Hawking, Jim Hartle etc... in the process of developing such ideas, if you want to pull out the credentials ploy) as the main point of his book, even if he doesn't spend a lot of time discussing his model (something I frankly doubt you can be the judge of at this stage).Alex Vilenkin, who has since become a friend, had actually just
written a paper that described in exactly this fashion how quantum
gravity indeed might create an inflating universe directly from nothing.
I was scooped, but I couldn't be that upset because (a) I frankly didn't
understand in detail at that point what I was doing, and (b) Alex
had the boldness to propose something that at the time I didn't.Yes, the model is based on unifying general relativity and QM ,
This is good, finally you're correcting your previous remarks. I wonder what the implications of this will actually be for you though, i.e. will you read Krauss with a bit less bias now that you actually understand where he is coming from?but I think the following quote from Vilenkin himself, is the key one that distinguishes for me the "quantum" versus "no quantum" argument. I don't accept, based on my reading of Vilenkin, that you can make the conclusion that quantum "kicked in" after the quantum tunneling event from an "empty geometry".
Well quite frankly we can't really base any conclusions off your reading since it's been so flawed & biased thus far. You really ought to re-read his book with an open mind & stop to research claim X or Y if you feel strongly enough about the subject.So, back to my original question; Where did the laws of physics, including the laws of QM, come from? They had to be there for this proposed quantum tunnelling event to happen.
Again if you'd read Krauss book with an open mind you'd see even Krauss takes a stab at this question:
I'll leave it to you to re-read his book, hopefully this time with an open mind, so that you can read the chapter beyond this statement to try to get Krauss' answer to your question.Does this prove that our universe arose from nothing? Of
course not. But it does take us one rather large step closer to the
plausibility of such a scenario. And it removes one more of the
objections that might have been leveled against the argument of
creation from nothing as described in the previous chapter.
There, "nothing" meant empty but preexisting space combined
with fixed and well-known laws of physics. Now the requirement
of space has been removed.
But, remarkably, as we shall next discuss , even the laws of
physics may not be necessary or required.
(Last paragraph of chapter 10)The charge of slander is a serious one and one you might consider withdrawing.
I've made the claim based on your own words & justified myself - you went off & grossly mischaracterized what I said, claiming I said it to counteract your disagreement with his philosophy when in fact I mentioned slander because you went off talking about quantum mechanics as the basis of his own theory despite the fact I've more than once given you evidence of Krauss explicitly saying "no quantum", & even went so far as to justify it. You might want to withdraw this request for me to withdraw what I said & maybe fess up to mischaracterizing both me & Krauss at this stage...The scientist whose work Krauss draws on does not make the conclusion that Krauss is arriving at, as in my opinion unlike Kraus he does not have an ideological ax to grind. Vilenkin clearly states in his own book that "nothing" as described in his model, is not absolute nothing.
Who cares if he does have an ideological axe to grind? If you sincerely thought about the implications of that sentence, like went into a field in the sun & stayed there until the moon came up just pondering the implications of approaching 'the other' you suspect of ulterior motives like this then I bet a world of new avenues would open up for you 0 -
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sponsoredwalk wrote: »Who cares if he does have an ideological axe to grind? If you sincerely thought about the implications of that sentence, like went into a field in the sun & stayed there until the moon came up just pondering the implications of approaching 'the other' you suspect of ulterior motives like this then I bet a world of new avenues would open up for you
Sounds like you've read the book since we last spoke. Perhaps you are right and I need to re-read it, its been a while. As I said my main issue is with Krauss' philosophy and not with the (highly speculative) science, and I admit I am a bit harsh on him, due to my bias of disliking scientists who use science to attack religious belief.
Anyway perhaps we will take this up later, or perhaps not:P, but good luck with the barbeque as if you are in Ireland such occasions are to be treasured;)0 -
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https://www.youtube.com/watch?v=F5zHXIlX0EU
I'll take your advice & chill out at a barbeque for a while in the real world & be back with a more laissez-faire attitude :cool: Advertisement