The presumed Invariance of the atom

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    Atom Invariance
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Discussion Overview

The discussion revolves around the concept of the invariance of atoms in physics, questioning whether this invariance is based on solid principles, laws, or experimental evidence. Participants explore the implications of assuming atomic invariance across time and space, touching upon theoretical and experimental aspects.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation

Main Points Raised

  • Some participants express skepticism about the presumed invariance of atoms, suggesting that it may be based on assumptions rather than established principles or laws.
  • Others argue that there are numerous experiments confirming the identical properties of atoms of a given element, citing atomic clocks as an example of precise measurements using cesium atoms.
  • A participant questions the validity of applying local measurements of atomic properties to atoms from the distant past, raising concerns about the lack of a law that guarantees their equivalence.
  • Another participant mentions theories suggesting that fundamental constants may vary with time or position, noting that experimental results so far have not detected such variations.
  • Some contributions highlight the importance of considering what is not included in existing tests of physical constants, arguing that the relationships between quantities and constants may not allow for independent variation.
  • One participant emphasizes that mainstream physics has conducted tests that fit both local and cosmic data without breaking known physical laws, suggesting that the outcomes of these tests should be acknowledged regardless of their implications.
  • A later reply questions the relevance of the topic to the Homework Help section, indicating a potential misunderstanding of the discussion's context.

Areas of Agreement / Disagreement

Participants generally do not reach a consensus, as multiple competing views remain regarding the nature of atomic invariance and the validity of existing experimental tests. The discussion reflects a range of opinions on the foundational principles of physics related to atomic properties.

Contextual Notes

Some limitations are noted, including the dependence on local lab frames for experiments and the unresolved nature of whether fundamental constants can vary. The discussion also highlights the complexity of relationships between physical quantities and constants.

heldervelez
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The physics building is based on the invariance of the atom.
Is there any principle or law or experiment ?
I think that we only presume.
What if there is no foundation for our 'truth' ?
 
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heldervelez said:
The physics building is based on the invariance of the atom.
Is there any principle or law or experiment ?
I think that we only presume.
What if there is no foundation for our 'truth' ?

If you are asking whether all atoms of a given element have identical properties (mass, charge, etc.), there are numerous experiments verifying that. For example the use of cesium atoms in atomic clocks, because of the precise frequency of one of the transitions in cesium.

We do not just "presume" in physics. The laws of physics do get tested experimentally, in fact performing these experiments is how many physicists earn a living.
 
All experiments are done in a local lab frame. Testing the general 'invariability' of the rulers we made with that atom can not be done from a local lab.
I agree with you that all atoms of a definite isotope that we can compare, at the same excitation level, seems fairly equal.

How can we be sure that an atom (H to simplify) from the distant past is 'equal' to the lab H?

What I think is that we use to apply the rulers to all times and positions, and I do not know a law/principle that validates the practice.
 
There is no law that says atoms in the distant past or at distant places are physically the same. There are theories that fundamental constants may vary with time or position. Does that make you happy? All you can do is make measurements to try to detect this variation. As far as I know, all of them, so far, come up negative.
 
What is not written can be very important.
And there are a natural trend to disregard what is left outside the papper.

All of the tests you mention are like:
There are 'tests' on the possible variation of 'c', 'G', 'alfa', and the test results are negative. None has achived a construction of a stable universe based in 'laws' where those constants (one at a a time ?, or combined,..) could be 'not constants'.

The exercise of varying things is pertinent because we have 3 basic physical equations and have more incognits (quantities M,L,T, and 'constants' epsilon,alfa,G,c)
The quantities are related to 'objects', say atoms, and constants are related to space (the way the space let thinghs go).

The 'tests' based on the quantities are doomed to fail, as they did, because there is something not written in the equations that matters:

We can not vary independently one or two of the quantities M,L,T, as they did in those tests. They can only vary at the same time because they are 'attached' to the 'atom scale'. It is so because it is the way we make 'rods', or rulers.

We will have a large/small 'metre' definition [L], and by 'c' constraint a larger/small time unit [T], naturally a 'large/small atom' will have a grater mass [M].

But this test was already made and claims to fit both local and cosmic data, with no break of known physical laws.

I think that those tests are mainstream physics, independent of the outcome 'fit/no fit', in particular if there is no break of laws.
 
heldervelez said:
What is not written can be very important.
And there are a natural trend to disregard what is left outside the papper.

All of the tests you mention are like:
There are 'tests' on the possible variation of 'c', 'G', 'alfa', and the test results are negative. None has achived a construction of a stable universe based in 'laws' where those constants (one at a a time ?, or combined,..) could be 'not constants'.

The exercise of varying things is pertinent because we have 3 basic physical equations and have more incognits (quantities M,L,T, and 'constants' epsilon,alfa,G,c)
The quantities are related to 'objects', say atoms, and constants are related to space (the way the space let thinghs go).

The 'tests' based on the quantities are doomed to fail, as they did, because there is something not written in the equations that matters:

We can not vary independently one or two of the quantities M,L,T, as they did in those tests. They can only vary at the same time because they are 'attached' to the 'atom scale'. It is so because it is the way we make 'rods', or rulers.

We will have a large/small 'metre' definition [L], and by 'c' constraint a larger/small time unit [T], naturally a 'large/small atom' will have a grater mass [M].

But this test was already made and claims to fit both local and cosmic data, with no break of known physical laws.

I think that those tests are mainstream physics, independent of the outcome 'fit/no fit', in particular if there is no break of laws.

This sort of thing really doesn't belong in the Homework Help section. Why did you feel a need to put it here?
 
heldervelez said:
The physics building is based on the invariance of the atom.
Is there any principle or law or experiment ?
At which university? Do you know who was the architect?
 

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