Thanks sle; who is the author?
There is ALWAYS a trade-off between theta and gamma. In other words, if you want to profit from positive theta, you CAN`T avoid negative gamma....
Short ATM straddle is delta neutral but has very high negative gamma (you have a negative gamma both on the short call and on the short put) ,...
How much is your call worth now? And the same call with 310$ strike?
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