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Small rewording
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For hyperbolic PDE's, we have two aspects that distinguish them from elliptic and parabolic PDE's and thus forbid one from being able to obtain estimates in the form you want:

  • Usually the loss of derivatives is worse than in the elliptic case — in fact, even worse than in the more general subelliptic case. Typically, you lose a full (weak = Sobolev) derivative in a priori regularity estimates for linear hyperbolic PDE's: the so-called energy estimates. This loss is essentially sharp and can be tracked back to the fundamental theorem of Calculus. As pointed by Willie Wong in his answer, this can be refined if you take into account the characteristic set of the principal symbol of the operator, by means of techniques collectively called microlocal analysis. More precisely, worse than elliptic-type regularity must propagate along the bicharacteristic curves of the principal symbol, which are nonexistent in the elliptic case.
  • Even if you account for the above loss of derivatives, the "optimal" relative shape of the regions $B_1$, $B_2$ is different due to a hallmark property of hyperbolic PDE's — namely, the finite speed of propagation of (perturbationssupports of) solutions. Typically, $B_2$ will be a "cone-shaped" shadow region cast by $B_1$, whose precise form is once again dictated by the principal symbol of the operator.

For hyperbolic PDE's, we have two aspects that distinguish them from elliptic and parabolic PDE's and thus forbid one from being able to obtain estimates in the form you want:

  • Usually the loss of derivatives is worse than in the elliptic case — in fact, even worse than in the more general subelliptic case. Typically, you lose a full (weak = Sobolev) derivative in a priori regularity estimates for linear hyperbolic PDE's: the so-called energy estimates. This loss is essentially sharp and can be tracked back to the fundamental theorem of Calculus. As pointed by Willie Wong in his answer, this can be refined if you take into account the characteristic set of the principal symbol of the operator, by means of techniques collectively called microlocal analysis. More precisely, worse than elliptic-type regularity must propagate along the bicharacteristic curves of the principal symbol, which are nonexistent in the elliptic case.
  • Even if you account for the above loss of derivatives, the "optimal" relative shape of the regions $B_1$, $B_2$ is different due to a hallmark property of hyperbolic PDE's — namely, the finite speed of propagation of (perturbations of) solutions. Typically, $B_2$ will be a "cone-shaped" shadow region cast by $B_1$, whose precise form is once again dictated by the principal symbol of the operator.

For hyperbolic PDE's, we have two aspects that distinguish them from elliptic and parabolic PDE's and thus forbid one from being able to obtain estimates in the form you want:

  • Usually the loss of derivatives is worse than in the elliptic case — in fact, even worse than in the more general subelliptic case. Typically, you lose a full (weak = Sobolev) derivative in a priori regularity estimates for linear hyperbolic PDE's: the so-called energy estimates. This loss is essentially sharp and can be tracked back to the fundamental theorem of Calculus. As pointed by Willie Wong in his answer, this can be refined if you take into account the characteristic set of the principal symbol of the operator, by means of techniques collectively called microlocal analysis. More precisely, worse than elliptic-type regularity must propagate along the bicharacteristic curves of the principal symbol, which are nonexistent in the elliptic case.
  • Even if you account for the above loss of derivatives, the "optimal" relative shape of the regions $B_1$, $B_2$ is different due to a hallmark property of hyperbolic PDE's — namely, the finite speed of propagation of (supports of) solutions. Typically, $B_2$ will be a "cone-shaped" shadow region cast by $B_1$, whose precise form is once again dictated by the principal symbol of the operator.
Link to @WillieWong's answer, while this is on the front page
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LSpice
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For hyperbolic PDE's, we have two aspects that distinguish them from elliptic and parabolic PDE's and thus forbid one from being able to obtain estimates in the form you want:

  • Usually the loss of derivatives is worse than in the elliptic case - in fact, even worse than in the more general subelliptic case. Typically, you lose a full (weak = Sobolev) derivative in a priori regularity estimates for linear hyperbolic PDE's: the so-called energy estimates. This loss is essentially sharp and can be tracked back to the fundamental theorem of Calculus. As pointed by Willie Wong in his answeranswer, this can be refined if you take into account the characteristic set of the principal symbol of the operator, by means of techniques collectively called microlocal analysis. More precisely, worse than elliptic-type regularity must propagate along the bicharacteristic curves of the principal symbol, which are nonexistent in the elliptic case.
  • Even if you account for the above loss of derivatives, the "optimal" relative shape of the regions $B_1,B_2$$B_1$, $B_2$ is different due to a hallmark property of hyperbolic PDE's - namely, the finite speed of propagation of (perturbations of) solutions. Typically, $B_2$ will be a "cone-shaped" shadow region cast by $B_1$, whose precise form is once again dictated by the principal symbol of the operator.

For hyperbolic PDE's, we have two aspects that distinguish them from elliptic and parabolic PDE's and thus forbid one from being able to obtain estimates in the form you want:

  • Usually the loss of derivatives is worse than in the elliptic case - in fact, even worse than in the more general subelliptic case. Typically, you lose a full (weak = Sobolev) derivative in a priori regularity estimates for linear hyperbolic PDE's: the so-called energy estimates. This loss is essentially sharp and can be tracked back to the fundamental theorem of Calculus. As pointed by Willie Wong in his answer, this can be refined if you take into account the characteristic set of the principal symbol of the operator, by means of techniques collectively called microlocal analysis. More precisely, worse than elliptic-type regularity must propagate along the bicharacteristic curves of the principal symbol, which are nonexistent in the elliptic case.
  • Even if you account for the above loss of derivatives, the "optimal" relative shape of the regions $B_1,B_2$ is different due to a hallmark property of hyperbolic PDE's - namely, the finite speed of propagation of (perturbations of) solutions. Typically, $B_2$ will be a "cone-shaped" shadow region cast by $B_1$, whose precise form is once again dictated by the principal symbol of the operator.

For hyperbolic PDE's, we have two aspects that distinguish them from elliptic and parabolic PDE's and thus forbid one from being able to obtain estimates in the form you want:

  • Usually the loss of derivatives is worse than in the elliptic case in fact, even worse than in the more general subelliptic case. Typically, you lose a full (weak = Sobolev) derivative in a priori regularity estimates for linear hyperbolic PDE's: the so-called energy estimates. This loss is essentially sharp and can be tracked back to the fundamental theorem of Calculus. As pointed by Willie Wong in his answer, this can be refined if you take into account the characteristic set of the principal symbol of the operator, by means of techniques collectively called microlocal analysis. More precisely, worse than elliptic-type regularity must propagate along the bicharacteristic curves of the principal symbol, which are nonexistent in the elliptic case.
  • Even if you account for the above loss of derivatives, the "optimal" relative shape of the regions $B_1$, $B_2$ is different due to a hallmark property of hyperbolic PDE's namely, the finite speed of propagation of (perturbations of) solutions. Typically, $B_2$ will be a "cone-shaped" shadow region cast by $B_1$, whose precise form is once again dictated by the principal symbol of the operator.
Added clarifying phrase
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For hyperbolic PDE's, we have two aspects that distinguish them from elliptic and parabolic PDE's and thus forbid one from being able to obtain estimates in the form you want:

  • Usually the loss of derivatives is worse than in the elliptic case - in fact, even worse than in the more general subelliptic case. Typically, you lose a full (weak = Sobolev) derivative in a priori regularity estimates for linear hyperbolic PDE's: the so-called energy estimates. This loss is essentially sharp and can be tracked back to the fundamental theorem of Calculus. As pointed by Willie Wong in his answer, this can be refined if you take into account the characteristic set of the principal symbol of the operator, by means of techniques collectively called microlocal analysis. More precisely, worse than elliptic-type regularity must propagate along the bicharacteristic curves of the principal symbol, which are nonexistent in the elliptic case.
  • Even if you account for the above loss of derivatives, the "optimal" relative shape of the regions $B_1,B_2$ is different due to a hallmark property of hyperbolic PDE's - namely, the finite speed of propagation of (perturbations of) solutions. Typically, $B_2$ will be a "cone-shaped" shadow region cast by $B_1$, whose precise form is once again dictated by the principal symbol of the operator.

For hyperbolic PDE's, we have two aspects that distinguish them from elliptic and parabolic PDE's:

  • Usually the loss of derivatives is worse than in the elliptic case - in fact, even worse than in the more general subelliptic case. Typically, you lose a full (weak = Sobolev) derivative in a priori regularity estimates for linear hyperbolic PDE's: the so-called energy estimates. This loss is essentially sharp and can be tracked back to the fundamental theorem of Calculus. As pointed by Willie Wong in his answer, this can be refined if you take into account the characteristic set of the principal symbol of the operator, by means of techniques collectively called microlocal analysis. More precisely, worse than elliptic-type regularity must propagate along the bicharacteristic curves of the principal symbol, which are nonexistent in the elliptic case.
  • Even if you account for the above loss of derivatives, the "optimal" relative shape of the regions $B_1,B_2$ is different due to a hallmark property of hyperbolic PDE's - namely, the finite speed of propagation of (perturbations of) solutions. Typically, $B_2$ will be a "cone-shaped" shadow region cast by $B_1$, whose precise form is once again dictated by the principal symbol of the operator.

For hyperbolic PDE's, we have two aspects that distinguish them from elliptic and parabolic PDE's and thus forbid one from being able to obtain estimates in the form you want:

  • Usually the loss of derivatives is worse than in the elliptic case - in fact, even worse than in the more general subelliptic case. Typically, you lose a full (weak = Sobolev) derivative in a priori regularity estimates for linear hyperbolic PDE's: the so-called energy estimates. This loss is essentially sharp and can be tracked back to the fundamental theorem of Calculus. As pointed by Willie Wong in his answer, this can be refined if you take into account the characteristic set of the principal symbol of the operator, by means of techniques collectively called microlocal analysis. More precisely, worse than elliptic-type regularity must propagate along the bicharacteristic curves of the principal symbol, which are nonexistent in the elliptic case.
  • Even if you account for the above loss of derivatives, the "optimal" relative shape of the regions $B_1,B_2$ is different due to a hallmark property of hyperbolic PDE's - namely, the finite speed of propagation of (perturbations of) solutions. Typically, $B_2$ will be a "cone-shaped" shadow region cast by $B_1$, whose precise form is once again dictated by the principal symbol of the operator.
Improved wording, added a bit of info on propagation of singularities
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