How did Niels Bohr obtain ΔT •ΔE > h?

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In summary, the experiment cannot proved that T3-T3﹥T4 T2, which means that the second reading Q is performed after photon emission and spring-balance rebalancing. Thus we can not concluded from the experiment that Q0-Q1=Q0-Q2, that is ΔM=M-m,ΔE=ΔMc2.
  • #1
Bomicro
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I mean when I deduct the Einstein’s box Bohr designed , I can not obtain the ΔT •ΔE > h like Bohr.

1) After balancing, the position of the spring-balance in weighing the box at the time 0 (T0) is Q0, and the weight of the box is M0. Because the experiment did not restrict the measuring accuracy of spring-balance position, so we suggested ΔQ≈0.

2) After rebalancing and the position of the spring-balance localized at Q2, we open the launch window at the time 1 (T1), and close it at he time 2 (T2). The total time (T) for photon to launch is equal to T2-T1; the distance the box moves in the direction of gravity is q; based on the general theory of relativity, the error of T2 we measured and the T (= T2-T1) we calculated is ΔT, and ΔT/ T = (1/c2) • g•Δq. Please pay attention, q≠ΔQ here.

3) The position of spring-balance in the second weighing of the box at time 3 (T3) is Q1, and the weight of the box is M1, the reduction weight of the box measured in the experiment, m, is equal to M0-M1.

4) At time 4 (T4), after rebalancing, the position of the spring-balance is Q2, and the actual decrease weight of the box M is equal to M1-M2.

The experiment can not proved that T3-T3﹥T4 T2, which means that the second reading Q is performed after photon emission and spring-balance rebalancing. Thus we can not concluded from the experiment that Q0-Q1=Q0-Q2, that is ΔM=M-m,ΔE=ΔMc2.

So how can Bohr calculate to obtain ΔT •ΔE > h?
 
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  • #2
Hi, Bomicro.

I have drawn the old book of mine from my bookshelf to review original Bohr's writings on the debate with Einstein. Two formula are essential.

Δp = h / Δq < T g Δm
where Δ express delta, Δp is width in measurement of vertical momentum of the box, h is Plack constant, Δq is width in measurement of measurement of vertical position of the box, T is time interval required to re-balance the box, g is acceleration by gravity of the Earth and Δm is change of weight or mass of the box by radiation.
This formula means that RHS T g Δm, which is impulse caused by emission of radiation from the box, must be larger than LHS the uncertainty of momentum of the box so that the energy or mass change can be measured.

ΔT/T = 1/c^2 g Δq
where ΔT is uncertainty of clock time caused by difference of gravity effect due to uncertainty of vertical position Δq during during re-balancing time interval T.

Combining two formulas we get ΔT > h/ c^2 Δm or ΔT ΔE > h.

I hope the above would be helpful to you in someway.

Regards.
 
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  • #3
Hi, sweet springs,
Thanks for the answer. However, I still have no idea about how Bohr perform the experiment to obtained this equation.
For example, what’s the reason that caused the vertical momentum of the box, that is p≠0 (if p=0, and will Δp =0?) Did it bring by the first reading of the position of the spring-balance in weighing the box at the time 0 (T0)? If the answer is yes, then we can read it after balancing, at this time, p is equal to 0, and Δp will equal to 0 too, and Δp = h / Δq < T g Δm will false. In addition, I think the experiment did not measure the vertical momentum of the box, so why Bohr introduce Δp = h / Δq?
If Δq (in ΔT/T = 1/c^2 g Δq) is the width in measurement of vertical position of the box (or uncertainty of vertical position), in the experiment, Δq will be a irrelevant constant, which is in contradiction with Δp = h / Δq < T g Δm.

Regards
 
  • #5
  • #6
Hi. Bomicro.

Bomicro said:
I want to know how to weighting the reduction of the box after photon emission using this apparatus by Bohr. For example, what time does it began to weight, how to weight, how many times he weight, and the measuring accuracy.

May I remind you that this is thought experiment which was thought out and investigated in debate between Bohr and Einstein, thus details of practical performance do not matter. You should focus your question on theoretical and principal points if you have.

Regards
 
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  • #7
It is not a good suggestion.
The details of practical performance are important in my opinion.
Because Bohr revised the details of Einstein’s box Einstein proposed firstly, and he believed the box must be placed on the spring-balance in the gravitational force.
 
  • #8
Hi, can anyone tell me the derivation of the formula "Δp = h / Δq < T g Δm" in detail?
Thank you very much!
 

1. How did Niels Bohr come up with the equation ΔT •ΔE > h?

Niels Bohr developed this equation as part of his atomic model in 1913. He was studying the behavior of electrons in atoms and their relationship to energy. Through his experiments and observations, he was able to derive this equation to explain the energy changes in atoms.

2. What does the equation ΔT •ΔE > h represent?

This equation represents the uncertainty principle, which is a fundamental concept in quantum mechanics. It states that the product of the uncertainty in time and the uncertainty in energy must be greater than or equal to the reduced Planck's constant, h.

3. How does ΔT •ΔE > h relate to quantum mechanics?

The uncertainty principle is a key principle in quantum mechanics, which is the branch of physics that studies the behavior of particles at the atomic and subatomic level. This equation shows that there is a limit to how precisely we can measure certain quantities, such as time and energy, in the quantum world.

4. Can ΔT •ΔE > h be applied to other systems besides atoms?

Yes, this equation can be applied to any system where there is a relationship between time and energy. It is a fundamental principle in quantum mechanics and is used in various fields such as particle physics, chemistry, and engineering.

5. How does ΔT •ΔE > h impact our understanding of the universe?

This equation has greatly impacted our understanding of the universe and the behavior of particles at the atomic level. It has led to the development of new technologies and has helped us to better understand the behavior of particles in various systems. It also highlights the inherent uncertainty and randomness in the quantum world, challenging our classical understanding of cause and effect.

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