Comparison Between Two Isolated Systems

In summary: But interesting question about how the radiation created by the annihilation would be affected by the gravity of the planet.
  • #1
J. Richter
9
0
If we think of two isolated systems, A and B, existing side by side, the proportion of the energy between those systems should always stay the same.

Here is a thought, that I would like some comments on:

System A contains a planet, and the advanced civilisation on this planet, have created a box with matter and antimatter ready to annihilate. Some electronic in the box will carry out this annihilation automatically, let’s say when the strength of the surrounding gravity field decreases below a certain limit.
Now, they are pushing this box out in the universe with the exact escape velocity of this planet.


The situation mentioned above, also happens in system B. The two systems are completely identical, except that the planet in system B has more mass, yet the same size.

So it is more “expensive” for the civilisation in system B, to push the box out in space, because of the higher escape velocity of this planet. It takes more energy.


Sometime in a very far future, the boxes will reach the decreased value of gravity that makes the matter and antimatter annihilate.

The two boxes will explode at exactly the same very low strength of gravity, and at very low speeds.

So, (that portion if not all) of the energy that is being converted from mass to electromagnetic radiation when the matter and antimatter annihilates, must be the same in the two systems.

How can the proportion between the energy in these two systems still be the same, as the civilisation in system B did spend more energy, pushing the box out in space?

Where and how in the two systems do we now see a change, that reflects and equalizes the two civilisations different use of energy, so that the proportion of the energy between system A and B will stay the same?
 
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  • #2
J. Richter said:
So, (that portion if not all) of the energy that is being converted from mass to electromagnetic radiation when the matter and antimatter annihilates, must be the same in the two systems.
OK, this is the energy contained in the boxes, not the energy of "the system".
How can the proportion between the energy in these two systems still be the same, as the civilisation in system B did spend more energy, pushing the box out in space?
Who said they were the same? Where does the energy to impart KE to the boxes come from? And when KE is given to the box, does that energy leave "the system"?
 
  • #3
Doc Al said:
OK, this is the energy contained in the boxes, not the energy of "the system".

Who said they were the same? Where does the energy to impart KE to the boxes come from? And when KE is given to the box, does that energy leave "the system"?

The boxes is not isolated systems themselves, so the energy contained in the boxes are part of the energy of the systems.

When the experiment starts there is a difference between the energy in system A and B, because the planet in system B has more mass. That difference should always be the same.

The energy of KE is not leaving. What appears to be leaving, (and is probably not), is the extra energy the civilisation in system B used, to carry out this experiment.
 
  • #4
J. Richter said:
When the experiment starts there is a difference between the energy in system A and B, because the planet in system B has more mass. That difference should always be the same.
What makes you think it changes?
The energy of KE is not leaving. What appears to be leaving, (and is probably not), is the extra energy the civilisation in system B used, to carry out this experiment.
That energy isn't lost, just transformed into increased gravitational PE.
 
  • #5
Doc Al said:
That energy isn't lost, just transformed into increased gravitational PE.

Increased gravitational PE between the planet and the box, yes.
When the box is gone, or part of it, what happens to the PE?

Who can now benefit from the PE?
 
  • #6
J. Richter said:
Increased gravitational PE between the planet and the box, yes.
When the box is gone, or part of it, what happens to the PE?
Since the box is "infinitely" far from the planet, you don't have to worry about PE any more.
Who can now benefit from the PE?
I suspect the folks back on the planet are quite happy to have given up energy (on the planet) to send that box sailing away before it exploded.

But interesting question about how the radiation created by the annihilation would be affected by the gravity of the planet.
 

1. What is the purpose of comparing two isolated systems?

The purpose of comparing two isolated systems is to understand their similarities and differences in terms of their properties, behavior, and interactions. This can provide insights into the underlying mechanisms and principles governing these systems, and help in making informed decisions about their use or management.

2. How do you define an isolated system?

An isolated system is a physical system that does not interact with its external surroundings in terms of energy or matter. This means that there is no exchange of energy or matter between the system and its surroundings, and the total energy and matter within the system remains constant over time.

3. What are the key factors to consider when comparing two isolated systems?

When comparing two isolated systems, it is important to consider their boundary conditions, initial state, and any external forces or constraints acting on them. Additionally, the properties and behavior of the systems, such as temperature, pressure, and volume, should also be taken into account.

4. Can two isolated systems be compared if they have different boundary conditions?

Yes, two isolated systems with different boundary conditions can still be compared. However, the comparison may need to be adjusted to account for the differences in boundary conditions, as these can affect the behavior and properties of the systems.

5. How do you ensure a fair comparison between two isolated systems?

To ensure a fair comparison between two isolated systems, it is important to control and minimize any external factors that may influence the systems. This can include controlling the initial state of the systems, keeping the boundary conditions consistent, and minimizing any external forces or constraints. Additionally, multiple trials and careful data analysis can help to reduce any potential bias in the comparison.

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