Regarding Schwartz inequality and integration bounds

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The discussion centers on the application of the Cauchy-Schwarz inequality to analyze the bounds of an integral involving functions A and Z. The key question is why the lower bound of integration includes the variable "s," leading to the inequality involving "s" rather than a simpler form without it. Participants clarify that the inclusion of "s" accounts for scenarios where it can be small, affecting the upper bound while maintaining mathematical correctness. The conversation emphasizes the balance between physical intuition and mathematical rigor in the context of integration bounds. Understanding this relationship is crucial for applying Schwartz inequality effectively in such scenarios.
p4wp4w
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Based on Schwartz inequality, I am trying to figure out why there
should/can be the "s" variable which is the lower bound of the
integration in the RHS of the following inequality:
## \left \|\int_{-s}^{0} A(t+r)Z(t+r) dr \right \|^{2} \leq s\int_{-s}^{0}\left \| A(t+r)Z(t+r) \right \|^{2} dr, ##
instead of:
## \left \|\int_{-s}^{0} A(t+r)Z(t+r) dr \right \|^{2} \leq \int_{-s}^{0}\left \| A(t+r)Z(t+r) \right \|^{2} dr. ##
 
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p4wp4w said:
Based on Schwartz inequality, I am trying to figure out why there
should/can be the "s" variable which is the lower bound of the
integration in the RHS of the following inequality:
## \left \|\int_{-s}^{0} A(t+r)Z(t+r) dr \right \|^{2} \leq s\int_{-s}^{0}\left \| A(t+r)Z(t+r) \right \|^{2} dr, ##
instead of:
## \left \|\int_{-s}^{0} A(t+r)Z(t+r) dr \right \|^{2} \leq \int_{-s}^{0}\left \| A(t+r)Z(t+r) \right \|^{2} dr. ##
Apply the Cauchy-Schwarz inequality to the functions##f,\ g## defined by ##f(r)=A(t+r)Z(t+r)## and ##g(r)=1##.
 
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Samy_A said:
Apply the Cauchy-Schwarz inequality to the functions##f,\ g## defined by ##f(r)=A(t+r)Z(t+r)## and ##g(r)=1##.
Sure. My confusion was because of the example in my mind that s can be a very small value which then the upper bound will be also very small and as a result, physically conservatism but again mathematically correct. Thank you very much.
 
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