user16771: I am having trouble understanding why the move e5 which I played in the position below
is not correct according to Stockfish (6th move for White)
I am not doing this move by winning a tempo, but I consider that this push would constrain Black particularly since d6 is no longer possible. and f6 would be quite weakening.
Another move I considered during the game (exd4 followed by d4) does not appear to be correct either. This way. I would prevent Black from further pushing their central pawns.

Could someone enlighten me in the pawn theory relevant to the diagram of the game?

user4418: e5 does nothing for you and helps your opponent. Why?
First, it does nothing for your development. Much better would be d3 which releases the c1 bishop and protects the e pawn. If your opponent plays de then you retake de and he is left with doubled isolated pawns on the c file and an isolated pawn on the a file. If he doesn't then exchange queens he also has an open position with his king still in the center and is behind in development.
Second, e5 releases the tension in the center and takes all the pressure off your opponent. His development becomes easy. He will play Bg4, exchange the light-squared bishop for your knight, block up the position with e6 and calmly complete his development.

user19877: I disagree that it is primarily about development.
This is a very common theme, and it comes down to the fact that e5 is not easily defended by a pawn (aka "artificially isolated"). Bg4 soon will trade one of the e5-pawn's defenders, and it will need constant watching. It is not a big deal that you will be trading the Bc8 on f3 since white already traded on c6 so you are not giving up the B-pair, and after e6, the c6-d5-e6 complex keeps a nice hold on the light squares.
Black can attack the e5-pawn with Qc7, and Ne7-g6 as one plan. If White defends with the obvious Re1 and Bf4 (and later Bg3 after Ng6), then Rb8; b3 will leave White's dark squares very weak.
It is also important to note that defending e5 with d4 is also never good after cxd4; any c5 and another pc5 appears and a nice center for Black.

16771: <p>I am having trouble understanding why the move e5 which I <a href="https://lichess.org/imeBM3Eu/white#10" rel="nofollow noreferrer">played</a> in the position below
is not correct according to Stockfish (6th move for White)</p>

<p>I am not doing this move by winning a tempo, but I consider that this push would constrain Black particularly since d6 is no longer possible. and f6 would be quite weakening.</p>

<p>Another move I considered during the game (exd4 followed by d4) does not appear to be correct either. This way. I would prevent Black from further pushing their central pawns.
<a href="https://i.stack.imgur.com/uzZ8l.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/uzZ8l.jpg" alt="enter image description here"></a></p>

<p>Could someone enlighten me in the pawn theory relevant to the diagram of the game?</p>
 4418: <p>e5 does nothing for you and helps your opponent. Why?</p>
<p>First, it does nothing for your development. Much better would be d3 which releases the c1 bishop and protects the e pawn. If your opponent plays de then you retake de and he is left with doubled isolated pawns on the c file and an isolated pawn on the a file. If he doesn't then exchange queens he also has an open position with his king still in the center and is behind in development.</p>
<p>Second, e5 releases the tension in the center and takes all the pressure off your opponent. His development becomes easy. He will play Bg4, exchange the light-squared bishop for your knight, block up the position with e6 and calmly complete his development.</p>
 19877: <p>I disagree that it is primarily about development.</p>
<p>This is a very common theme, and it comes down to the fact that e5 is not easily defended by a pawn (aka &quot;artificially isolated&quot;). Bg4 soon will trade one of the e5-pawn's defenders, and it will need constant watching. It is not a big deal that you will be trading the Bc8 on f3 since white already traded on c6 so you are not giving up the B-pair, and after e6, the c6-d5-e6 complex keeps a nice hold on the light squares.</p>
<p>Black can attack the e5-pawn with Qc7, and Ne7-g6 as one plan. If White defends with the obvious Re1 and Bf4 (and later Bg3 after Ng6), then Rb8; b3 will leave White's dark squares very weak.</p>
<p>It is also important to note that defending e5 with d4 is also never good after cxd4; any c5 and another pc5 appears and a nice center for Black.</p>
