Originally posted by zanket
Is there such a thing as a pure vacuum? Or is it thought that every portion of the universe no matter how small is completely full of energy, such as quantum foam, virtual particles or electromagnetic waves?
Originally posted by ScRaMbLe
What the hell is going on here?!!! I go to bed, wake up this morning and all of a sudden the more respected physics posters are acknowledging zero point energy?!! Did I fall into an alternate reality while I was sleeping? Don't get me wrong, I'm so glad you guys are accepting the concept, but WTF? What changed your minds?
Originally posted by zanket
So far the answer seems to be “no, arguably.” Are physicists really so divided about this or am I just misunderstanding what I’m reading here? When I read about vacuum energy, I see no mention of it being observed within an arbitrarily small volume, like that of a subatomic particle. It's more believable that it exists within larger volumes.
Crisp – I define a pure vacuum as a space void of any energy.
yes this is a correct view IMO. There can be no moment before time began. Nor can there be any moments after time ceases. So if the universe should end it will do so as if it never had existed in the first place as no historical remnant will remain to demonstrate it.Quantum, you said something very interesting ... you said, "BEFORE" big bang; I remember that Space and time are connected (general theory of relativity I believe), so there CANNOT be any thing BEFORE big bang, because time is a conception tightly coupled with space; off course I am a noob to everything, so i could be completely wrong, if so; please excuse me.
Rick
And your logic for this is.....?Absolute nothing = absolute vacuum. Absolute vacuum is inverse energy therefore absolute vacuum is infinite energy.
Except that isn't how it works, a vacuum isn't attractive. If you opened the door on the Shuttle you aren't sucked out by the 'attractive' properties of the vacuum, you're blown out by the high pressure of the air in the Shuttle. The air is applying an outwards pressure and when you remove the constraint holding the air in (ie open a door) then it'll blast out. The same is true for your body, the fluid and gases are held in because there's an equalising pressure on the other side of your skin due to the atmosphere. If you removed that your blood and lung air wouldn't be sucked out of you, it'd be forcing its way out of you.The absence of pressure means that it has an incredably strong attraction to anything that has pressure and this I believe is gravity, the effect of the attraction ofabsolute vacuum or in other words absolute nothing.
In the centre of everything is absolute nothing ( vacuum ) which by default is extremely attractive.
We shouldn't "hedge" when it comes to defining "Pure Vacuum". It should be nothing..period.
agreed , absolutely
If you observe energy of any kind within a fixed volume then you do not have a "Pure Vacuum". You have something else. You have a semi-perfect vacuum. Pure vacuum contains nothing. Maybe we could argue whether Pure Vacuum can be contained within a vessel? But the Universe is not a vessel. It is infinite. I like leaving "Pure Vacuum" as a completely empty volume and instead arguing about how pure it can be and still be observed by our rudimentary instruments.
agreed
Vacuum is energy without doubt......just inverse. (My thoughts)