Statistics: Degeneracy and Multiplicity

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Homework Help Overview

The discussion revolves around a problem involving drawing a card from a standard deck, focusing on concepts of microstates, macrostates, degeneracy, and multiplicity within the context of statistics and thermodynamics.

Discussion Character

  • Conceptual clarification, Assumption checking, Mixed

Approaches and Questions Raised

  • Participants explore definitions of microstates and macrostates, questioning their application to the card-drawing scenario. Some suggest there may be two macrostates based on suit and rank, while others consider the total number of cards as microstates. There is also discussion about the differences between degeneracy and multiplicity.

Discussion Status

The conversation includes various interpretations of the terms and their relevance to the problem. Some participants express uncertainty about the definitions and the appropriateness of using a deck of cards as an analogy for thermodynamic concepts. Guidance is offered to contact the instructor for clarification on the definitions and the problem setup.

Contextual Notes

Participants note that the problem may not align well with standard definitions in probability and that the instructor's clarity on the topic is lacking, leading to confusion regarding the answers.

teme92
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Homework Statement



Consider drawing one card from a deck with no jokers or other special cards.
a) What is the number of microstates? (4/13/52/cant tell)
b) What is the number of macrostates?(4/13/52/cant tell)
c) What is the degeneracy of macrostate spade? (4/13/52/cant tell)
d) What is the multiplicity of the macrostate King? (4/13/52/cant tell)

Homework Equations

The Attempt at a Solution



a) I said the number of microstates is equal to the number of cards types (Ace,2,3...K) so 13

b)Macrostates is equal to number of suits so 4

c)Dengeneracy of spades is equal to number of cards in spades so 13

d)I'm not sure but was thinking 4 because there are 4 kings in a deck

Could anyone please tell me if these are correct or if I am looking at it in the wrong way. Any help is much appreciated!
 
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teme92 said:

Homework Statement



Consider drawing one card from a deck with no jokers or other special cards.
a) What is the number of microstates? (4/13/52/cant tell)
b) What is the number of macrostates?(4/13/52/cant tell)
c) What is the degeneracy of macrostate spade? (4/13/52/cant tell)
d) What is the multiplicity of the macrostate King? (4/13/52/cant tell)
How are the terms microstate, macrostate, and degeneracy defined? These are not standard terms in probability.
teme92 said:

Homework Equations

The Attempt at a Solution



a) I said the number of microstates is equal to the number of cards types (Ace,2,3...K) so 13
Without knowing how your text defines micro/macrostate, I'd be inclined to think that there might be two macrostates: suit and rank. With the same thinking, there would be 52 microstates.
teme92 said:
b)Macrostates is equal to number of suits so 4

c)Dengeneracy of spades is equal to number of cards in spades so 13
How is degeneracy different from multiplicity?
teme92 said:
d)I'm not sure but was thinking 4 because there are 4 kings in a deck

Could anyone please tell me if these are correct or if I am looking at it in the wrong way. Any help is much appreciated!
 
Hey Mark44, thanks for the reply.

This is question for my Intro to Thermodynamics and Statistical Physics module but the problem is more general statistics.

A microstate is a specific microscopic configuration of a thermodynamic system that the system may occupy with a certain probability in the course of its thermal fluctuations. In contrast, the macrostate of a system refers to its macroscopic properties, such as its temperature and pressure.

In systems with multiple quantum states s sharing the same Es, it is said that the energy levels of the system are degenerate.

You said that there is two macrostates when you commented on part a) but in part b) there is no answer option for 2?
 
Mark44 said:
How are the terms microstate, macrostate, and degeneracy defined? These are not standard terms in probability.
Without knowing how your text defines micro/macrostate, I'd be inclined to think that there might be two macrostates: suit and rank. With the same thinking, there would be 52 microstates.
How is degeneracy different from multiplicity?

teme92 said:
Hey Mark44, thanks for the reply.

This is question for my Intro to Thermodynamics and Statistical Physics module but the problem is more general statistics.

A microstate is a specific microscopic configuration of a thermodynamic system that the system may occupy with a certain probability in the course of its thermal fluctuations. In contrast, the macrostate of a system refers to its macroscopic properties, such as its temperature and pressure.

In systems with multiple quantum states s sharing the same Es, it is said that the energy levels of the system are degenerate.

You said that there is two macrostates when you commented on part a) but in part b) there is no answer option for 2?

He did not say 2, he said 52.

Anyway, applying some of these concepts to a deck of cards seems like an inappropriate 'reach'. What are the energy levels of a card or a deck of cards?

Some of these concepts have differently-named versions in probability: "microstates" = sample space (at least in sufficiently fine-grained models) and "macrostates" = events in a partition of the sample space.
 
teme92 said:
Hey Mark44, thanks for the reply.

This is question for my Intro to Thermodynamics and Statistical Physics module but the problem is more general statistics.

A microstate is a specific microscopic configuration of a thermodynamic system that the system may occupy with a certain probability in the course of its thermal fluctuations. In contrast, the macrostate of a system refers to its macroscopic properties, such as its temperature and pressure.

In systems with multiple quantum states s sharing the same Es, it is said that the energy levels of the system are degenerate.

You said that there is two macrostates when you commented on part a) but in part b) there is no answer option for 2?
I said that I thought there might be two macrostates. Two macro properties of the cards would seem to me to be suit and rank. Questions c and d suggest that both suit and rank are macrostates. I can't explain why 2 isn't a possible answer, but I can't justify 4, 13, or 52, and "can't tell" doesn't seem to apply.

The module is using a deck of cards as an analog for a thermodynamic system, but I still don't understand how "degenerate" ties into cards. For question d, I believe the multiplicity of "King" is four, since there are four Kings, and I think that the multiplicity of "spade" is 13, since there are 13 spades, but how multiplicity and degeneracy are different, I don't understand.

If I were you I would contact the instructor to get his/her take on this.
 
Ok thanks guys for the help. I don't understand fully myself as there is no mention of this in any of the lectures. I'll just give him the answers I think are correct and tell him its his fault, for not being clear, if they are wrong :P
 
If these are questions he wrote himself, as opposed to ones that appear in the textbook, it could be that not all of them were as well thought-out as they should be. It has happened before...
 
No they aren't out of a textbook. They're on a sheet he handed out.
 
teme92 said:
No they aren't out of a textbook. They're on a sheet he handed out.
All the more reason to contact him, either in person or by email. You could tell him that you think the answers are (or should be) such and such, and give your reasoning.
 
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  • #10
Mark44 said:
I said that I thought there might be two macrostates. Two macro properties of the cards would seem to me to be suit and rank. Questions c and d suggest that both suit and rank are macrostates. I can't explain why 2 isn't a possible answer, but I can't justify 4, 13, or 52, and "can't tell" doesn't seem to apply.

I was thinking of part (a), where you did give the 52 answer.

The module is using a deck of cards as an analog for a thermodynamic system, but I still don't understand how "degenerate" ties into cards. For question d, I believe the multiplicity of "King" is four, since there are four Kings, and I think that the multiplicity of "spade" is 13, since there are 13 spades, but how multiplicity and degeneracy are different, I don't understand.

If I were you I would contact the instructor to get his/her take on this.
 
  • #11
Ok, thanks again!
 

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