Skip to main content
Notice removed Improve details by Alfred
Bounty Ended with Neil Strickland's answer chosen by Alfred
Notice added Improve details by Alfred
Bounty Started worth 50 reputation by Alfred
added 93 characters in body
Source Link
Alfred
  • 899
  • 5
  • 16

QUESTION EDITED: There was a mistake, the spectrum i had written before didn't even exist, so a big thanks to the people who made me notice that in the comments.

Let $X_n$ be the spectrum such that $BP_*(X_n) = BP_*/(v_0^{p^{i_0}},v_1^{p^{i_1}},\dots,v_{n-1}^{p^{i_{n-i}}})$$BP_*(X_n) = \Sigma^{d_n}BP_*/(v_0^{p^{i_0}},v_1^{p^{i_1}},\dots,v_{n-1}^{p^{i_{n-i}}})$. Recall that it's always possible to have a sequence $i_0, i_1, i_2 \dots$ such that a spectrum with the given BP-homology exists (this was my mistake before editing the question). $d_n$ is a natural number big enough which makes $X_i$ be a suspension spectrum.

Let also $X = \bigvee_i X_i$.

Now consider the following fibration:

$ \bigvee_i X_i \to L_n \bigvee X_i \to \Sigma C_n \bigvee X_i $

which gives me the following inverse system of short exact sequences:

$$ 0 \to \bigoplus_{i \leq n} BP_*(X_i) \longrightarrow \ \bigoplus_{i \leq n} BP_*L_n(X_i) \ \longrightarrow \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to 0$$

$$ 0 \to \bigoplus_{i \leq n-1} BP_*(X_i) \to \bigoplus_{i \leq n-1} BP_*L_{n-1}(X_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{n-1}X_i) \to 0$$

with vertical maps $$ \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{i-1}X_i)$$

So here is my second question: How can i study the inverse limit of the right vertical tower $$lim_n \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i)?$$

Thank you

QUESTION EDITED: There was a mistake, the spectrum i had written before didn't even exist, so a big thanks to the people who made me notice that in the comments.

Let $X_n$ be the spectrum such that $BP_*(X_n) = BP_*/(v_0^{p^{i_0}},v_1^{p^{i_1}},\dots,v_{n-1}^{p^{i_{n-i}}})$. Recall that it's always possible to have a sequence $i_0, i_1, i_2 \dots$ such that a spectrum with the given BP-homology exists (this was my mistake before editing the question).

Let also $X = \bigvee_i X_i$.

Now consider the following fibration:

$ \bigvee_i X_i \to L_n \bigvee X_i \to \Sigma C_n \bigvee X_i $

which gives me the following inverse system of short exact sequences:

$$ 0 \to \bigoplus_{i \leq n} BP_*(X_i) \longrightarrow \ \bigoplus_{i \leq n} BP_*L_n(X_i) \ \longrightarrow \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to 0$$

$$ 0 \to \bigoplus_{i \leq n-1} BP_*(X_i) \to \bigoplus_{i \leq n-1} BP_*L_{n-1}(X_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{n-1}X_i) \to 0$$

with vertical maps $$ \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{i-1}X_i)$$

So here is my second question: How can i study the inverse limit of the right vertical tower $$lim_n \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i)?$$

Thank you

QUESTION EDITED: There was a mistake, the spectrum i had written before didn't even exist, so a big thanks to the people who made me notice that in the comments.

Let $X_n$ be the spectrum such that $BP_*(X_n) = \Sigma^{d_n}BP_*/(v_0^{p^{i_0}},v_1^{p^{i_1}},\dots,v_{n-1}^{p^{i_{n-i}}})$. Recall that it's always possible to have a sequence $i_0, i_1, i_2 \dots$ such that a spectrum with the given BP-homology exists (this was my mistake before editing the question). $d_n$ is a natural number big enough which makes $X_i$ be a suspension spectrum.

Let also $X = \bigvee_i X_i$.

Now consider the following fibration:

$ \bigvee_i X_i \to L_n \bigvee X_i \to \Sigma C_n \bigvee X_i $

which gives me the following inverse system of short exact sequences:

$$ 0 \to \bigoplus_{i \leq n} BP_*(X_i) \longrightarrow \ \bigoplus_{i \leq n} BP_*L_n(X_i) \ \longrightarrow \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to 0$$

$$ 0 \to \bigoplus_{i \leq n-1} BP_*(X_i) \to \bigoplus_{i \leq n-1} BP_*L_{n-1}(X_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{n-1}X_i) \to 0$$

with vertical maps $$ \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{i-1}X_i)$$

So here is my second question: How can i study the inverse limit of the right vertical tower $$lim_n \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i)?$$

Thank you

The spectrum i had before didn't even exist
Source Link
Alfred
  • 899
  • 5
  • 16

QUESTION EDITED: There was a mistake, the spectrum i had written before didn't even exist, so a big thanks to the people who made me notice that in the comments.

Let $X_i$$X_n$ be the spectrum such that $BP_*(X_i) = \Sigma^{i+1} BP_* / (v_0^2, v_1^2 , \dots, v_{i-1}^2)$ and$BP_*(X_n) = BP_*/(v_0^{p^{i_0}},v_1^{p^{i_1}},\dots,v_{n-1}^{p^{i_{n-i}}})$. Recall that it's always possible to have a sequence $X = \bigvee_i X_i$$i_0, i_1, i_2 \dots$ such that a spectrum with the given BP-homology exists (this was my mistake before editing the question).

First question: Can i always say that $X$ andLet also $X_i$ are suspension spectra? Why?$X = \bigvee_i X_i$.

Now let's consider the following fibration:

$ \bigvee_i X_i \to L_n \bigvee X_i \to \Sigma C_n \bigvee X_i $

which gives me the following inverse system of short exact sequences:

$$ 0 \to \bigoplus_{i \leq n} BP_*(X_i) \longrightarrow \ \bigoplus_{i \leq n} BP_*L_n(X_i) \ \longrightarrow \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to 0$$

$$ 0 \to \bigoplus_{i \leq n-1} BP_*(X_i) \to \bigoplus_{i \leq n-1} BP_*L_{n-1}(X_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{n-1}X_i) \to 0$$

with vertical maps $$ \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{i-1}X_i)$$

So here is my second question: How can i study the inverse limit of the right vertical tower $$lim_n \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i)?$$

Thank you

Let $X_i$ be the spectrum such that $BP_*(X_i) = \Sigma^{i+1} BP_* / (v_0^2, v_1^2 , \dots, v_{i-1}^2)$ and $X = \bigvee_i X_i$.

First question: Can i always say that $X$ and $X_i$ are suspension spectra? Why?

Now let's consider the following fibration:

$ \bigvee_i X_i \to L_n \bigvee X_i \to \Sigma C_n \bigvee X_i $

which gives me the following inverse system of short exact sequences:

$$ 0 \to \bigoplus_{i \leq n} BP_*(X_i) \longrightarrow \ \bigoplus_{i \leq n} BP_*L_n(X_i) \ \longrightarrow \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to 0$$

$$ 0 \to \bigoplus_{i \leq n-1} BP_*(X_i) \to \bigoplus_{i \leq n-1} BP_*L_{n-1}(X_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{n-1}X_i) \to 0$$

with vertical maps $$ \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{i-1}X_i)$$

So here is my second question: How can i study the inverse limit of the right vertical tower $$lim_n \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i)?$$

Thank you

QUESTION EDITED: There was a mistake, the spectrum i had written before didn't even exist, so a big thanks to the people who made me notice that in the comments.

Let $X_n$ be the spectrum such that $BP_*(X_n) = BP_*/(v_0^{p^{i_0}},v_1^{p^{i_1}},\dots,v_{n-1}^{p^{i_{n-i}}})$. Recall that it's always possible to have a sequence $i_0, i_1, i_2 \dots$ such that a spectrum with the given BP-homology exists (this was my mistake before editing the question).

Let also $X = \bigvee_i X_i$.

Now consider the following fibration:

$ \bigvee_i X_i \to L_n \bigvee X_i \to \Sigma C_n \bigvee X_i $

which gives me the following inverse system of short exact sequences:

$$ 0 \to \bigoplus_{i \leq n} BP_*(X_i) \longrightarrow \ \bigoplus_{i \leq n} BP_*L_n(X_i) \ \longrightarrow \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to 0$$

$$ 0 \to \bigoplus_{i \leq n-1} BP_*(X_i) \to \bigoplus_{i \leq n-1} BP_*L_{n-1}(X_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{n-1}X_i) \to 0$$

with vertical maps $$ \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{i-1}X_i)$$

So here is my second question: How can i study the inverse limit of the right vertical tower $$lim_n \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i)?$$

Thank you

Source Link
Alfred
  • 899
  • 5
  • 16

Studying the limit of a sequence of spectra knowing their BP-Homology

Let $X_i$ be the spectrum such that $BP_*(X_i) = \Sigma^{i+1} BP_* / (v_0^2, v_1^2 , \dots, v_{i-1}^2)$ and $X = \bigvee_i X_i$.

First question: Can i always say that $X$ and $X_i$ are suspension spectra? Why?

Now let's consider the following fibration:

$ \bigvee_i X_i \to L_n \bigvee X_i \to \Sigma C_n \bigvee X_i $

which gives me the following inverse system of short exact sequences:

$$ 0 \to \bigoplus_{i \leq n} BP_*(X_i) \longrightarrow \ \bigoplus_{i \leq n} BP_*L_n(X_i) \ \longrightarrow \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to 0$$

$$ 0 \to \bigoplus_{i \leq n-1} BP_*(X_i) \to \bigoplus_{i \leq n-1} BP_*L_{n-1}(X_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{n-1}X_i) \to 0$$

with vertical maps $$ \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i) \to \bigoplus_{i \leq n-1} BP_{*-1}(\Sigma C_{i-1}X_i)$$

So here is my second question: How can i study the inverse limit of the right vertical tower $$lim_n \bigoplus_{i \leq n} BP_{*-1}(\Sigma C_iX_i)?$$

Thank you