Science a GoGo's Home Page Forums General Discussion Physics Forum Can David Bohm explain the double slit experiment?

If I said that space and time are illusions that allow us to make sense of the Universe in which we live, you would probably think I was saying that space and time are not real. Such would certainly not be the case. Those things we perceive, measure and experience are real; to claim otherwise would be to retreat into some sort of mystical solipsism. You will not find me there, unless I'm winding someone up.

This takes us back to your:



Exchanging “eternal” for “perpetual”, I would say two things:

1. You live in linear time, so unless you could establish a beginning for a specific object, how would you know it had a beginning? You might argue that if you could see it, it must be part of the Universe, so must have had a beginning. That’s valid, but only as a distinction between infinite cosmos and finite Universe, which gets you no further forward.

2. Not being able to “see” a beginning is not proof of an eternal state. James Hutton’s concept of geological time found “No vestige of a beginning, no prospect of an end.” However, later work has established that geological time is certainly not infinite, or even unbounded in either direction.

Your second assertion, that you “have never seen something suddenly created from nothing” is certainly what I would expect, especially if you are referring to absolute nothing, rather than to some pseudo nothing that might exist alongside something.

The vital question that needs answering, without prevarication, is: If there had ever been (absolutely) nothing, could there be something now?

Yes to all of that and I have no evidence I would be prepared to rely on.


Technically a universe is a little stricter definition you have things clumped in relationships. There is no way I can test such a thing so by putting a horizon there you don't get involved in making assumptions, very similar to event horizon on a black hole.


If you know the history of string theory both of them got merged into a large on called M-string theory which allows both at same time. So it's even more complex time loops back on itself and you have brane horizons.


Scientifically if time extends the mathematics of string theory would be right. Really string theory is just a full formalization of relativity in every degree of freedom including time.

I am not as sold on the strings themselves you take a leap of faith to say this is how it is encoded when you cant test it.

Do I believe it well lets say I am luke warm.

Orac, you stopped short of the "vital question".

"The vital question that needs answering, without prevarication, is: If there had ever been (absolutely) nothing, could there be something now?"

Bill S,

I've seen no reason to change my opinion (which was no).

(As long as you continue to use the qualifier "absolutely", as some
scientists seem to have their own definition of "nothing".)

Pokey, it's a refreshing change to get a straight answer to that question.

I did get a straight "Yes" on another forum. Naturally, I asked for an explanation, which I'm still waiting for. It's about a year now, so I guess it's not coming.

BTW, I object to using "absolute(ly)" with nothing and infinite, as with perfect, complete etc. but, as you point out, it is becoming necessary.

Yes and No .... the question can't be answered without making assumptions and you have no basis to make any assumption.

Let me be clear on the problem and expand it

Scientifically all we can state is time is something that is encoded as a change of state. As I was explaining to Bill S technically space and time are the two sides of the same thing. Could there be more, well yes and we have actually done it

http://www.extremetech.com/extreme/16228...-quantum-memory

That sets a crystal up to maintain the quantum coherence and bingo time is suspended for the poor unsuspecting photon.

Now lets make this interesting and talk about the only thing in human world that has basically grown from nothing to something which is economics. I have discussed before there is a lot in common between economics and energy.

The beginning of economics is easy to deal with a person with excess of something traded it for something they needed in a barter exchange. The something weird happened some bright spark decided to make a promisery exchange, he promised to make good on something in the future but he wanted the other persons goods now. That concept exploded and now most people walk down to the shop with there promisery note (AKA dollars) and buy there goods they need. There is also no sign that economics is limited they seem to be able to expand forever.

The interesting thought for you is if we forgot about the bartering and people just started promisery exchanges would the system work and the answer is clearly yes. It is also valid to think of the quantum waveform as the promisery note between events, see everyone has to pay there way.

So all we need in the energy domain is a promisery exchange to initiate everything

We have zero energy is that nothing?
(+x) energy + (-x) energy still equals zero energy ... still nothing isn't it .. or is it something now?

Mathematically all these are equivalents but are they nothing?
0 = 1 - 1 = 1000 - 1000 = -30 + 30 = 10 elephants - 10 elephants

I tried to get Bill S to see this issue that you still could be nothing, it depends on ones definition

Ok so what's going on in all that, well it's the same problem as economics it's about locality and moment in time and QM controls both. You can't measure anything without energy, that underpins your something and nothing definitions and QM holds all the cards and promisery notes.

So bluntly your definition of something and nothing can not be made universal and you have no right to do so. The best I can guess is you are trying to use philosophical definitions of nothing and something not scientific.

I need you to prove universal something and nothing, and you aren't the photon trapped in the crystal to me

The answer is YES/NO/MAYBE/WHO CARES take your pick they are all equally right until you have a theory of everything. My suggestion is believe whatever you want it's fine and makes no difference to anything. It might interest a philosophical person but little interest to science.

So lets put out the challenge can anyone prove to me that the sum of energy in any object (chose any one you like) is anything other than net total of zero?

I put one restriction no cheating and using temporary Quantum states

We will leave whether an object with net zero energy is something or nothing to a later discussion

Bill S for you lets extend you, because you are at that point, can any object have absolute zero kinetic energy and absolute zero gravitational energy?

Orac, that is sort of what I meant about prevarication. Your arguments are faultless, they sound convincing, but are completely meaningless in terms of the basic discussion.

Economics did not start from nothing, it started from beings undertaking exchanges. That is relevant only if you redefine beings, and the world in which they live as nothing.



All that this establishes is that the excess energy in that system is zero; but unless x=0, you have to have two lots of something to balance your equation.



This is pure mathematical flapdoodle. In the physical world, how do you make 10 elephants become nothing? Isn’t there something in the laws of physics……….?



“locality”, “time”, “QM”, “energy”, “cards” and “promissory notes” are all examples of something. You can juggle them in any way you like, no combination of them will ever be nothing, nor will it be relevant to the something/nothing discussion.



It is scientists who talk about whether or not the Universe could emerge from nothing. I have introduced no topic that I have not found in the literature published by scientists.

When a scientist can say “By nothing, I do not mean nothing…..”, then I guess that’s a signpost that points to “the flapdoodle campaign, in which more and more ado is made about less and less.”

No; nor can any object be nothing; unless you redefine nothing to mean something, which makes the whole discussion pointless.

This is a bit like trying to make a religious fanatic keep to a rational like of thought, or persuade a rabid atheist that agnosticism is the only logical stance for a scientist. Actually, that can be fun.

That is actually the point.

Essentially from a science point of view you are arguing a ghost is "something" how do I measure such a thing?

There never was nothing, there was nothing and still is nothing, there is no such thing as nothing ..... they are the same thing to me.

It seems important to you so I will just agree but it isn't very useful from a science standpoint.

I would be interested in an science paper that proposes something from nothing given nothing can you point me at one. Scientifically you can only define nothing as the absence of a constituent and I will be curious how they did that.

Orac, do you seriously think I am trying to say that nothing is something?



That’s a fascinating insight into the way you think about nothing/something.

There is no such thing as nothing. Obviously true. A “thing” must be something.
There never was nothing. Arguably true, but there is no consensus.
There was nothing and still is nothing. Untrue. Manifestly there is something now.

How can you see all these as the same?

Perhaps it's time for some clarity regarding my position on the subject of nothing.

Nothing is the absence of absolutely everything: no matter, no energy, no QM, no potential.

Although the term is used in many limited/limiting ways, and may have reached a point where it is necessary to qualify it as “absolutely nothing”; it is the above sense in which I use it, unless qualified for some specific reason.

There are various “clever” arguments that one meets in the course of discussion. I’ve never actually met this one, but it has the requisite “smartarse” touch. Absolutely nothing can have no certainty; it can also have no uncertainty, but if we can say with certainty that it has no uncertainty, then it must have certainty. If we cannot say that with certainty, then it must have uncertainty. Which does it have? Of course, this is pure semantics. It is not worthy of scientific discussion, but there are many arguments out there that are less obviously empty words, but amount to the same thing.

For nothing to become something, or something to become nothing would necessitate the violation of the laws of physics.

That is something science can not accept because I can not test for it. The only way to arrive at your concept of nothing is to exclude every other option and I can't. In principle I can agree that an area has none of the things you list but that still takes me short of calling it nothing. You know about the conjecture of quintessence how would I exclude things like that scalar field being there?

Science has the situation of predicting dark matter but unable to find it, and not having a full theory for gravity. You also saw how hidden the Higgs field was and what it took to make it testable.

So can I realistically ask would it be safe for science to say anything conclusive about the concept of nothing?


Again whilst I agree with the thrust of the thought you forget that is true of the universe we measure and see here and now. The problem is the big bang directly contradicts that statement in that we have a huge amount of energy come into existence.

So we are left with two choices, one of which I think is the one you have selected

1.) The energy that came into the universe from the big bang came from something before/outside the big bang or something in physics we have not yet understood. This says the law of conservation always and absolutely holds.

2.) The laws of physics have not been constant throughout the history of the universe. The conservation law does not hold in some epochs of physics but it is valid and holds in our current epoch.

Science is actually in favour of 2 because of how the fundamental forces seem behave as you increase the scale of energy. As the energy is increased the various forces seem to merge together and so it leads to a prediction that all the fundamental forces merge to just one at the point of the big bang (https://en.wikipedia.org/wiki/Grand_unification_epoch).

It is hard to determine what physics looks like in such a epoch and that includes whether the law of conservation is going to hold. Most guesses are conservation doesn't hold because the whole thing looks like it is unstable.

So I would like you to tell me how and why you exclude option 2?
How safe do you feel you are in excluding 2 without any data from that epoch?

I should say I can shortcut and explain why they favour 2 and the issue (which is time) or I am happy to just prompt questions and you will arrive at the problem by following the logic.

Of course you can’t call it nothing. If you are talking about “an area” you are not talking about nothing! A scalar field is something, so if you are talking about a situation in which there could be a field, you are not talking about nothing.



You are totally and consistently missing (or evading) the point. I do not exclude 2, or 1. If there were nothing there would be no epochs, no laws of physics and no options and no numbers with which to label them.



No problem with that, but surely you are not suggesting that this says anything about what might have preceded the BB. The points you make are good, they are just irrelevant because they all involve something.

I don’t need there to be a thing called “nothing”; even the suggestion of that is absurd.

There is no “nothing”. Nothing doesn’t exist. Of course science can’t test for it, it doesn’t exist. If “nothing” doesn’t exist, there cannot be “nothing”, nor can there ever have been “nothing”.

BTW, how did we get from the double slit experiment to nothing?

We got here because you know have enough understanding now to get to an issue. This issue causes problems for layman and crackpots because they don't take the effort to resolve an issue and that is Energy and Time. Those two things are needed to resolve the concept of nothing. Ok I will have a crack at it.

Historically when it was first realized classical physics was wrong science had to deal with sort of closing off classical physics so it was consistent as best it could be. GR itself actually gets caught up in this because of energy and time in it's definitions.

So here is a statement of fact if you are using classical physics you must assume conservation of energy of the universe as a whole. If you are using QM you must assume the universe doesn't have conservation of energy, the universe is a perpetual energy machine. So how can two completely different statements both be right?

Well it rolls on definition .. surprise!!! Classical physics has time-translation invariance, the thing Dave Proffitt was playing with. It basically says things like space and time are fixed, not changing with time (and time itself is static) and running a physical interaction backward is the same as running it forward. You saw Dave realized something that it might be important with his playing with black holes.

GR joined time and space together and suddenly you break that condition, spacetime is no longer invariant. So when you are using GR as an interface to classical physics the trick to do is put any none classic energy in the gravitational field itself to stop classic physics imploding. Is it actually valid to do that well yes so long as the problem you are looking at isn't the universe itself, it won't cause you any problems.

So there is nothing wrong with saying GR conserves energy for most of your science, and it won't cause you any dramas but you need to remember what you did.

When we cross over to QM we have to deal with this there is no density of a gravitational field to place the energy in, yeah it really was a trick. We also need to deal with the fact spacetime is evolving, space and time are both changing or can change. Spacetime will likely expand or shrink, the static condition requires an unnatural balancing act. Think of a country economy growing at exactly zero for any prolonged length of years that is the same highly unlikely situation.

What you want in classical physics is the energy to be "worth" a static and consistent amount. So when your photon takes off with a set amount of energy it arrives at a destination some billion years later with the same amount of energy or all the classical laws are going to collapse. In an expanding universe and with classic physics definitions your photon takes off and your universe expands so your energy density decreases (you have more space to fill with the same energy) and your photon appears redshifted so it really is losing energy and then it gets to the destination some billion years later and magically it has the same energy as it left. This usually causes fun trying to watch even scientists explain it and they usually end up lying.

So how does QM-GR resolve the above well you are talking about an observer and what he sees ... it's an observer they see there own reality. The photons reality is it arrives at the destination in exactly zero seconds and hence it contains the same energy as when it left.

Even when dealt with well it's problematic, lets give you an example:
http://www.fnal.gov/pub/science/inquiring/questions/red_shift1.html

Do you spot the omission in the answer, you can't have a reference frame for the universe so he didn't really answer the question posed. What he did was restore conservation as the question was asked by someone only backgrounded in classical physics. From his answer it is clear to me he knows the full answer he is just trying to simplify it back to the OP.

This is my problem with your "nothing" I have been trying to give it back to you in a way you can deal with in your semi classical physics you are currently using. You keep using me and you references and what we see ... well we see a great many strange things because we are observers.

In essence you are doing the same trick as Dave Proffit imposing your little biased "observer view" as some proxy for the universe as a whole. My warning remains the same as to Dave be VERY CAREFUL doing this you are just a pathetic little observer you don't speak for the universe.

So lets see if you can get the concept just because you see nothing or something just makes it real to you, NOT the universe. Same problem as our little photon, you see the photons losing energy doesn't make it a universal truth. You have got your head around the frame of reference issue for time in GR, you now need to extend that to taking care with any observation you seek to make universal.

From a QM point of view and in your terms the universe can go from minus a pile of something thru zero to positive a pile of something. Is minus something okay with you in that it probably isn't what you would call something but it also isn't zero. If I can have that then I can sort of agree with your statement.

My concern isn't about your definition (you seem to think it is), it is after getting you to think relativity the first thing you have now gone and done is put a big absolute in the middle and called it "nothing". So I am seeking clarification on what observer or are you really trying to say that for everyone AKA what Dave does with time.

Thanks Orac, there's some good stuff there which needs some thought and which I will return to.



No; if there were really nothing, there would be no SR, GR or QM for it to be in the middle of. There is no "nothing". I am not inventing it; it doesn't exist.

While doing my thinking, I would be very interested to have the comments of those more experienced than I on this video.

https://www.youtube.com/watch?v=W9yWv5dqSKk


My reaction is that it says no more about QM than the ball and sheet demonstration says about gravity. Possibly it says less.

The action of the droplets and waves is maintained by the vibration of the underlying plate. We are not told if this vibration is constant, or varied. If it is constant, why would patterns of movement develop?

If the waves are generated by the presence and bouncing of the particles, why would the two not move together?

Saying that the waves appear to guide the particles is just a matter of interpretation; it could as well be the other way round; or neither could be guiding the other.

I see no indication of interference patterns developing when a particle passes through a slit. In fact the wave always seems to go through the same slit as the particle.

I was actually stunned that was less QM than many other experiments you could create. What I saw was more like the classical interpretation of particle/wave behaviour not much else but I guess it was a class one wave which is really what they were describing.

As Matt Strassler pointed out there aren't a lot of studies of class 1 waves in classical physics so I guess they are at least getting there head around the properties and what they found amazing.

I did chuckle that they really didn't understand the double slit experiment enough to get it to work correctly those slits needed to be a lot closer to get the waveforms moving thru the slits to self interfere.

I pretty much agree with you not much QM similarity there

With your other nothing situation, that is fine then. It worried me you were getting dangerously close to doing a Dave on me and declaring just because I observe something it's a universal truth. As I said I think your statement is probably correct but do so with extreme care because I can't really test it.

Couldn't the observation of something now be considered a test of the statement: "Nothing does not exist"?