Understanding Sylow's First Theorem to Prime Power Subgroups

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In summary: This is also restated as a finite group G whose order |G| is divisible by a prime power p^k has a subgroup of order p^k. These two statements may seem different, but they both guarantee the existence of subgroups of prime power order. The book has a slightly stronger statement, stating that for any p-group of order p^k, there is a subgroup of order p^j for 0 <= j <= k. This can be proven using induction and the fact that p-groups have non-trivial centers, which have subgroups of order p for every prime that divides the order of the group.
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doubleaxel195
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I'm getting a little confused about what exactly Sylow's first theorem says.

On Wikipedia, it says that Sylow's First Theorem says "For any prime factor p with multiplicity n of the order of a finite group G, there exists a Sylow p-subgroup of G, of order p^n."

Then in the section of the proof it is restated as "A finite group G whose order |G| is divisible by a prime power p^k has a subgroup of order p^k."

To me, these seem like they are saying two different things. The first seems like its only guaranteeing subgroups of prime power where the prime power is maximal (p^k where |G|=p^km where p does not divide m), while the second seems to be saying there are subgroups of order p^1, p^2, p^3, ... p^(k-1), p^k. Am I misunderstanding something?
 
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The book has a slightly stronger statement as Sylow's Theorem than what the wikipedia article says. However, if P is a p-group of order p^k then there is a subgroup of order p^j for 0 <= j <= k. To prove this, you can use induction and the fact that p-groups have non-trivial centers and the fact that abelian groups (you can only use abelian properties for the center) have subgroups of order p for every prime that divides the order of the group (there is probably an exercise or this is a theorem where this fact is proven).
 
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Sylow's firs theorem is basically saying that for any prime factor p with multiplicity n of the order of a finite group G, there exists a Sylow p-subgroup of G, of order p^n.
 

FAQ: Understanding Sylow's First Theorem to Prime Power Subgroups

What is Sylow's First Theorem?

Sylow's First Theorem is a mathematical theorem named after the Norwegian mathematician Ludwig Sylow. It states that if a finite group has a prime power order, then it must contain a subgroup of that prime power order.

What is the significance of Sylow's First Theorem?

Sylow's First Theorem is significant because it provides a way to analyze the structure of finite groups. It allows us to break down a group into smaller subgroups, which can simplify the understanding and computation of the group's properties.

Can you provide an example of Sylow's First Theorem in action?

Sure, let's consider a group G with order 36. Since 36 is a multiple of 3, we know that G must have at least one subgroup of order 3, as per Sylow's First Theorem. This subgroup can then be further analyzed to understand the properties of the larger group G.

What are the conditions for Sylow's First Theorem to apply?

For Sylow's First Theorem to apply, the group in question must have a prime power order, meaning that its order must be a product of prime numbers. Additionally, the theorem only applies to finite groups, not infinite ones.

How does Sylow's First Theorem relate to other theorems in group theory?

Sylow's First Theorem is closely related to other theorems in group theory, such as Lagrange's Theorem and Cauchy's Theorem. It builds upon these theorems and provides a more specific and useful result for analyzing the structure of finite groups.

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