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The question looks like an exercise in elementary algebraic topology, but I didn't manage to solve it. I am considering this question because it is a toy example in a problem I'm thinking about.

Let's consider the natural embedding $GL_n(\mathbb C) \to \mathbb C^{n^2} \backslash \{0\}$. As was discussed in this questionin this question, cohomology with rational coefficients of $GL_n(\mathbb C)$ is an exterior algebra on generators in degrees 1, 3, ..., 2n-1 (one generator in each degree), whereas $\mathbb C^{n^2} \backslash \{0\}$ is homotopy equivalent to a sphere $S^{n^2-1}$.

I'd like to prove that the map induced on cohomology of degree $n^2 - 1$ is a zero map. Any ideas?

Thanks.

The question looks like an exercise in elementary algebraic topology, but I didn't manage to solve it. I am considering this question because it is a toy example in a problem I'm thinking about.

Let's consider the natural embedding $GL_n(\mathbb C) \to \mathbb C^{n^2} \backslash \{0\}$. As was discussed in this question, cohomology with rational coefficients of $GL_n(\mathbb C)$ is an exterior algebra on generators in degrees 1, 3, ..., 2n-1 (one generator in each degree), whereas $\mathbb C^{n^2} \backslash \{0\}$ is homotopy equivalent to a sphere $S^{n^2-1}$.

I'd like to prove that the map induced on cohomology of degree $n^2 - 1$ is a zero map. Any ideas?

Thanks.

The question looks like an exercise in elementary algebraic topology, but I didn't manage to solve it. I am considering this question because it is a toy example in a problem I'm thinking about.

Let's consider the natural embedding $GL_n(\mathbb C) \to \mathbb C^{n^2} \backslash \{0\}$. As was discussed in this question, cohomology with rational coefficients of $GL_n(\mathbb C)$ is an exterior algebra on generators in degrees 1, 3, ..., 2n-1 (one generator in each degree), whereas $\mathbb C^{n^2} \backslash \{0\}$ is homotopy equivalent to a sphere $S^{n^2-1}$.

I'd like to prove that the map induced on cohomology of degree $n^2 - 1$ is a zero map. Any ideas?

Thanks.

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Evgeny Shinder
  • 1.8k
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The question looks like an exercise in elementary algebraic topology, but I didn't manage to solve it. I am considering this question because it is a toy example in a problem I'm thinking about.

Let's consider the natural embedding $GL_n(\mathbb C) \to \mathbb C^{n^2} \backslash \{0\}$. As was discussed in this question, cohomology with rational coefficients of $GL_n(\mathbb C)$ is an exterior algebra on generators in degrees 1, 23, ..., n2n-1 (one generator in each degree), whereas $\mathbb C^{n^2} \backslash \{0\}$ is homotopy equivalent to a sphere $S^{n^2-1}$.

I'd like to prove that the map induced on cohomology of degree $n^2 - 1$ is a zero map. Any ideas?

Thanks.

The question looks like an exercise in elementary algebraic topology, but I didn't manage to solve it. I am considering this question because it is a toy example in a problem I'm thinking about.

Let's consider the natural embedding $GL_n(\mathbb C) \to \mathbb C^{n^2} \backslash \{0\}$. As was discussed in this question, cohomology with rational coefficients of $GL_n(\mathbb C)$ is an exterior algebra on generators in degrees 1, 2, ..., n (one generator in each degree), whereas $\mathbb C^{n^2} \backslash \{0\}$ is homotopy equivalent to a sphere $S^{n^2-1}$.

I'd like to prove that the map induced on cohomology of degree $n^2 - 1$ is a zero map. Any ideas?

Thanks.

The question looks like an exercise in elementary algebraic topology, but I didn't manage to solve it. I am considering this question because it is a toy example in a problem I'm thinking about.

Let's consider the natural embedding $GL_n(\mathbb C) \to \mathbb C^{n^2} \backslash \{0\}$. As was discussed in this question, cohomology with rational coefficients of $GL_n(\mathbb C)$ is an exterior algebra on generators in degrees 1, 3, ..., 2n-1 (one generator in each degree), whereas $\mathbb C^{n^2} \backslash \{0\}$ is homotopy equivalent to a sphere $S^{n^2-1}$.

I'd like to prove that the map induced on cohomology of degree $n^2 - 1$ is a zero map. Any ideas?

Thanks.

added 25 characters in body
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Evgeny Shinder
  • 1.8k
  • 14
  • 30

The question looks like an exercise in elementary algebraic topology, but I didn't manage to solve it. I am considering this question because it is a toy example in a problem I'm thinking about.

Let's consider the natural embedding $GL_n(\mathbb C) \to \mathbb C^{n^2} \backslash \{0\}$. As was discussed in this question, cohomology with rational coefficients of $GL_n(\mathbb C)$ is an exterior algebra on generators in degrees 1, 2, ..., n (one generator in each degree), whereas $\mathbb C^{n^2} \backslash \{0\}$ is homotopy equivalent to a sphere $S^{n^2-1}$.

I'd like to prove that the map induced on cohomology of degree $n^2 - 1$ is a zero map. The question looks like an exercise in elementary algebraic topology, but I didn't manage to prove it. I am considering this question because it is a toy example in a problem I'm thinking about Any ideas?

Thanks.

Let's consider the natural embedding $GL_n(\mathbb C) \to \mathbb C^{n^2} \backslash \{0\}$. As was discussed in this question, cohomology with rational coefficients of $GL_n(\mathbb C)$ is an exterior algebra on generators in degrees 1, 2, ..., n (one generator in each degree), whereas $\mathbb C^{n^2} \backslash \{0\}$ is homotopy equivalent to a sphere $S^{n^2-1}$.

I'd like to prove that the map induced on cohomology of degree $n^2 - 1$ is a zero map. The question looks like an exercise in elementary algebraic topology, but I didn't manage to prove it. I am considering this question because it is a toy example in a problem I'm thinking about.

The question looks like an exercise in elementary algebraic topology, but I didn't manage to solve it. I am considering this question because it is a toy example in a problem I'm thinking about.

Let's consider the natural embedding $GL_n(\mathbb C) \to \mathbb C^{n^2} \backslash \{0\}$. As was discussed in this question, cohomology with rational coefficients of $GL_n(\mathbb C)$ is an exterior algebra on generators in degrees 1, 2, ..., n (one generator in each degree), whereas $\mathbb C^{n^2} \backslash \{0\}$ is homotopy equivalent to a sphere $S^{n^2-1}$.

I'd like to prove that the map induced on cohomology of degree $n^2 - 1$ is a zero map. Any ideas?

Thanks.

Source Link
Evgeny Shinder
  • 1.8k
  • 14
  • 30
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