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LSpice
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For a pure-injective module $M$ does the property "$Hom"$\operatorname{Hom}(-,M)$ is surjective" commute with certain limits?

Let$\DeclareMathOperator\Hom{Hom}$Let $M$ be a pure-injective module. Then $Hom(\varphi,M)$$\Hom(\varphi,M)$ is surjective for a pure-mono $\varphi$. It is well-known that $\varphi$ is a direct limit of split monos $\varphi_i$ between finitely presented modules. Clearly all $Hom(\varphi_i, M) $$\Hom(\varphi_i, M) $ are surjective. This motivates the following question:

Let $M$ be a pure-injective module, $\psi_i$ a directed system of monos between finitely presented modules and $\psi$ the direct limit of this system. If all $Hom(\psi_i, M)$$\Hom(\psi_i, M)$ are surjective, does it follow that $Hom(\psi, M)$$\Hom(\psi, M)$ is surjective?

For a pure-injective module $M$ does the property "$Hom(-,M)$ is surjective" commute with certain limits?

Let $M$ be a pure-injective module. Then $Hom(\varphi,M)$ is surjective for a pure-mono $\varphi$. It is well-known that $\varphi$ is a direct limit of split monos $\varphi_i$ between finitely presented modules. Clearly all $Hom(\varphi_i, M) $ are surjective. This motivates the following question:

Let $M$ be a pure-injective module, $\psi_i$ a directed system of monos between finitely presented modules and $\psi$ the direct limit of this system. If all $Hom(\psi_i, M)$ are surjective, does it follow that $Hom(\psi, M)$ is surjective?

For a pure-injective module $M$ does the property "$\operatorname{Hom}(-,M)$ is surjective" commute with certain limits?

$\DeclareMathOperator\Hom{Hom}$Let $M$ be a pure-injective module. Then $\Hom(\varphi,M)$ is surjective for a pure-mono $\varphi$. It is well-known that $\varphi$ is a direct limit of split monos $\varphi_i$ between finitely presented modules. Clearly all $\Hom(\varphi_i, M) $ are surjective. This motivates the following question:

Let $M$ be a pure-injective module, $\psi_i$ a directed system of monos between finitely presented modules and $\psi$ the direct limit of this system. If all $\Hom(\psi_i, M)$ are surjective, does it follow that $\Hom(\psi, M)$ is surjective?

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kevkev1695
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For a pure-injective module $M$ does the property "$Hom(-,M)$ is surjective" commute with certain limits?

Let $M$ be a pure-injective module. Then $Hom(\varphi,M)$ is surjective for a pure-mono $\varphi$. It is well-known that $\varphi$ is a direct limit of split monos $\varphi_i$ between finitely presented modules. Clearly all $Hom(\varphi_i, M) $ are surjective. This motivates the following question:

Let $M$ be a pure-injective module, $\psi_i$ a directed system of monos between finitely presented modules and $\psi$ the direct limit of this system. If all $Hom(\psi_i, M)$ are surjective, does it follow that $Hom(\psi, M)$ is surjective?