Does the Type of vaccum matter?

In summary, the current theory is that the universe has no boundaries and it is unclear if the laws of physics apply at the boundaries, if they exist. Light can travel within our universe, but it is not able to escape it due to the lack of a true vacuum. The concept of a finite, boundaryless universe can be understood by thinking of it as curving back on itself in 3D, similar to a balloon in 2D. This means that a light beam will always stay within our universe and not encounter any boundaries.
  • #1
madphysics
61
0
If light can travel through a vacuum, what's to keep it from traveling out of the "boundaries" of the universe?

If it can, Why doesn't it?

If it can't, what is out their must be something other than a vacuum, or the light can't travel in a vacuum.




Right?
 
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  • #2
According to present theory, the universe has no boundaries.
 
  • #3
We don't really know about the boundaries of the universe, or if there are or are not boundaries, or if the physical laws as we understand them even apply at the boundaries.
 
  • #4
If light travels there, it is in our universe.
 
  • #5
But still, what keeps light from "escaping" our universe? Is it the fact that their is no true vacuum in which we can prove light does travel?
 
  • #6
mathman said:
According to present theory, the universe has no boundaries.

Really?

I was under the immpresion that for something to grow in size, it had to have prevu=iuos boundaries to grow past.
 
  • #7
madphysics said:
Really?

I was under the immpresion that for something to grow in size, it had to have prevu=iuos boundaries to grow past.


The usual picture is the two dimensional analog, the surface of a balloon, which can get bigger with no boundary.
 
  • #8
Wouldn't that still imply something to grow into?
 
  • #9
It likely would, yes. One example is a fourth dimension. But that doesn't mean light can travel through it.


The easiest way to think about a finite boundaryless universe is to think of it curving back on itself in 3D, like the balloon does in 2D. If a light beam heads in a straight line long enough, it simply arrives back at its starting point. It has not left our universe, nor has it encountered any sort of boundary.
 
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1. What is the difference between bagged and bagless vacuums?

The main difference between bagged and bagless vacuums is the way they collect and contain dirt and debris. Bagged vacuums use disposable bags to collect dirt, while bagless vacuums have a built-in dustbin that can be emptied and reused.

2. Does the type of vacuum affect its cleaning performance?

Yes, the type of vacuum can affect its cleaning performance. Bagged vacuums generally have better suction power since the dirt is collected in a sealed bag, preventing it from escaping back into the air. However, bagless vacuums can maintain their suction power longer since the dustbin can be emptied when it becomes full.

3. Are there any environmental considerations when choosing a vacuum type?

Yes, there are environmental considerations when choosing a vacuum type. Bagged vacuums produce more waste since the bags need to be disposed of after each use. On the other hand, bagless vacuums can be more eco-friendly since they do not require disposable bags.

4. Can the type of vacuum affect indoor air quality?

Yes, the type of vacuum can affect indoor air quality. Bagged vacuums tend to have better filtration systems since the dirt and debris are collected in a sealed bag. This prevents dust and allergens from being released back into the air. However, bagless vacuums can also have high-quality filtration systems that can effectively trap dust and allergens.

5. Is one type of vacuum better than the other?

It ultimately depends on personal preference and specific needs. Bagged vacuums may be better for those with allergies or asthma since they have better filtration systems. Bagless vacuums may be more convenient and eco-friendly. It is important to consider factors such as suction power, filtration, and maintenance when choosing a vacuum.

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