Is there a place in space where there is no energy?

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Discussion Overview

The discussion revolves around the concept of energy in space, specifically questioning whether there are regions in space devoid of energy. Participants explore related ideas such as the visibility of stars, the energy density of gravitational fields, and the implications of measuring energy in different contexts.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants question if there is a place in space with no energy, linking this to the visibility of stars and the nature of gravitational fields.
  • One participant argues that measuring a region inherently adds energy, suggesting that it is impossible to determine if a region is devoid of energy.
  • Another participant challenges the idea of adding energy when observing a star, seeking clarification on the interaction between observation and energy.
  • There is a mention of the omnipresence of starlight and the fact that space is not at absolute zero, implying that energy is pervasive.
  • One participant concludes that energy is everywhere, raising a question about the source of energy in the context of an expanding universe.

Areas of Agreement / Disagreement

Participants express differing views on the nature of energy in space, with no consensus reached on whether regions devoid of energy exist or how energy interacts with observation.

Contextual Notes

The discussion highlights the complexity of defining "space" and "energy," as well as the challenges in measuring energy in different contexts, which remain unresolved.

cragar
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This may be a dumb question . My friend asked me is there a place in space where there is no energy .And then he said
is there a place in space where you can't see any stars . Do gravitational fields have energy densities .
So is there a place in space that has no energy ?
 
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cragar said:
This may be a dumb question . My friend asked me is there a place in space where there is no energy .And then he said
is there a place in space where you can't see any stars . Do gravitational fields have energy densities .
So is there a place in space that has no energy ?

You can't test whether or not a region is devoid of energy. As soon as you measure something, you add energy to it. If you can't test a theory, it's not scientific.
 
Tac-Tics said:
You can't test whether or not a region is devoid of energy. As soon as you measure something, you add energy to it. If you can't test a theory, it's not scientific.

If I am observing a star through a telescope, how am I adding energy to that star?
 
if you think about the size of your eye's iris, and the amount of starlight that enters it on a cloudless night, then think that some star light (energy) is also passing through just about every millimeter of space. Space isn't at absolute zero either.
 
pallidin said:
If I am observing a star through a telescope, how am I adding energy to that star?

You're definitely interacting with the star when the light hits your eye. Maybe I'm playing fast and loose, equating "space" with "system".

If you're taking a measuring on a region of space (and not a system of particles), you have the additional difficulty that your measurement must be made instantaneously. By naming spatial bounding box for a region in your coordinate system, you can specify what "space" you're talking about. But an instant later, it's unclear whether or not the same bounding box refers to the "same space".
 
so then energy is everywhere.
 
If energy is everywhere , and space is expanding , then where does this energy come from to fill the void .
 

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