# List of Questions I want to ask regarding physics, philosophy, mathematics, etc.

1. Jun 8, 2012

### ConfusedSoul

Dear Peeps,

How are you guys doing? Please forgive me if the title is to vague but I am new on this website and I am confused about some concepts I picked up while reading some of the threads here.

I consider myself a layman kind of, Im actually studying aerospace engineering and I have got 2nd year level modern physics background (I know its pretty small). So if you guys could help me understand some concepts it would be nice.

1). Concept of Infinity and Nothingness, its mathematical and Physical Application

First of I would like to say that i treat these terms as followed:
Infinite - Something having no limits or bounds
Nothingness - An Absence of Something, Void, Not a thing

As well I consider these definition subjective and not absolute.

So most of my confusion came from this thread

Now I have got a theory, that is "infinity" and "nothingness" don't really exist but there concept does. Like how infinity as a mathematical concept exist but as an object doesn't exist, same thing as nothingness, its concept exist and is widely used in many forms but as an object doesn't exist (due to it contradicting itself, as if nothing exist then it is something). And that we can't truly comprehend it (or experience it). As well if there is a "beyond" our universe (assuming everything is in our universe) relative to this universe, the beyond is just nothingness. As in that No thing (and thing pertains to entities in the universe) exist outside. Now I can assume there is actually creation or existence outside this universe (and I may not understand it and it may in fact be "infinite") but relative to the universe it is no thing. Does thing make sense, if not where is my flaw?

Now the confusion arises because in the forum alot of people jump back and fourth, and I am trying to find proof to my logic. As I understand it there is an agreed consensus that infinity may or may not exist. And assuming if that infinity exist, it can effectively expand. I understand that mathematically if sets A and B are both "infinite" and are not the same, then combining them to make Set C is basically the equivalent of Set A expanding to Set B. So basically all 3 sets are still infinite and no logic has been broken but effectively it has expanded. Since it can infact expand and if the universe is infinite, then the so called paradox doesn't exist and this expansion is seen when two objects observe a change in distance between them.

So I am wondering if my logic makes sense and if it can be used to prove my own theory? As well, in physics, does infinite really mean very large or does it actually mean limitless?

2). Is creation and destruction possible in the absolute sense?

My question here is that the laws of the universe says that effectively mass, energy and charge cannot be created or destroyed, only transferred. Does that mean inside this universe creation (bringing and entity into existence) and destruction (removing an entity out of existence) in the absolute sense is impossible? So does that mean when matter/energy enters a black hole does it then just get shredded into smaller and smaller pieces as it enter the singularity? As well I was reading upon the concept of hawkings radiation and virtual particles. To my understanding these particles appear in the "vacuum" because of the uncertainty of the energy density, I believe it is due to spikes in quantum fluctuation. So do physicist believe that these particles are created in the vacuum out of nothing (thus violating the law of the universe) or do these virtual particles show up to counter-act the fluctuations in energy?

3). Singularity and Gamma Ray Bursts

My final question is inspired by some you tube videos. So from what I recall, singularity is a single point consisting or "everything". And a black hole is basically a gravitational singularity due to the star gaseous core falling into itself effectively warping space time. Some say this extreme warping is almost breaking space time, is that even possible? As well, is gravity really infinite there or just very large? And is it possible for mass to occupy zero volume? or is it just really close to zero? As well, form what I understand a GRB happens when the Black Hole "chokes" as in since it eats up matter slowly, the tidal forces heat up the gas so much that it becomes plasma AFAIK so how does this heating up release huge amounts of Gamma Ray's at once, shouldn't it be a gradual release and not a burst? Or am I just confused? :P

4). Concept of 4-D

AFAIK, spatial dimensions go like this (mathematically) so 1D is a point, 2D is a line, 3D is a plane (lines connecting each other in both parallel and perpendicular orientation?) and 4D would just be a extension of 2D but with planes correct? So how did scientist come up with the idea of simplifying the geometry of our 4D universe as 3 spatial dimension and 1 temporal dimension? As well mathematically can time be a dimension? Described using geometric axioms? Or am I missing something?

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So basically if you guys can help me understand these concept it would be a great help. My goal was to take humanity to a higher platform in science and engineering and I have great interest in this (effectively I am looking for answers) and I would like motivate myself more, thus I am asking these questions. Thanks.

2. Jun 8, 2012

### Muphrid

1) Sure, I would say in the physical world we can never realize infinite anything or total nothingness. We use these as idealizations that are pretty good when something is, say, only "really far" instead of "infinitely far" or when space has only one atom per cubic centimeter instead of being total vacuum (i.e. nothing).

2) Sure, I would say that nothing is created or destroyed. It all just gets transformed. Even the mass that goes into a black hole eventually (over a long period of time) leaks out as Hawking radiation.

3) The question of what actually happens precisely at a singularity is one that physicists have been working on for the better part of a century. I don't know enough about GRBs to answer that.

4) 1D is a line, 2D is a plane, 3D is a volume, 4D is that volume with an additional perpendicular dimension. I'd say the first serious consideration that time should be treated as a fourth dimension dates back to Minkowski (though others thought of it before, this, I think, is where the modern notion comes from).