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In mathematics, the Schauder estimates are a collection of results due to Template:Harvs concerning the regularity of solutions to linear, uniformly elliptic partial differential equations. The estimates say that when the equation has appropriately smooth terms and appropriately smooth solutions, then the Hölder norm of the solution can be controlled in terms of the Hölder norms for the coefficient and source terms. Since these estimates do not assume the existence of the solution, they are called a priori estimates.

There is both an interior result, giving a Hölder condition for the solution in interior domains away from the boundary, and a boundary result, giving the Hölder condition for the solution in the entire domain. The former bound depends only on the spatial dimension, the equation, and the distance to the boundary; the latter depends on the smoothness of the boundary as well.

The Schauder estimates are a necessary precondition to using the method of continuity to proving the existence and regularity of solutions to the Dirichlet problem for elliptic PDEs. This result says that when the coefficients of the equation and the nature of the boundary conditions are sufficiently smooth, there is a smooth classical solution to the PDE.

Notation

The Schauder estimates are given in terms of weighted Hölder norms; the notation will follow that given in the text of Template:Harvs.

The supremum norm of a continuous function $f \in C (Ω)$ is given by

| f |_{0; Ω} = \sup_{x \in Ω} | f (x) |

For a function which is Hölder continuous with exponent $α$ , that is to say, $f \in C^{α} (Ω)$ the usual Hölder seminorm is given by

[f]_{0, α; Ω} = \sup_{x, y \in Ω} \frac{| f (x) - f (y) |}{| x - y |^{α}} .

The sum of the two is the full Hölder norm of f

| f |_{0, α; Ω} = | f |_{0; Ω} + [f]_{0, α; Ω} = \sup_{x \in Ω} | f (x) | + \sup_{x, y \in Ω} \frac{| f (x) - f (y) |}{| x - y |^{α}} .

For differentiable functions u, it is necessary to consider the higher order norms, involving derivatives. The norm in the space of functions with k continuous derivatives, $C^{k} (Ω)$ , is given by

| u |_{k; Ω} = \sum_{| β | \leq k} \sup_{x \in Ω} | D^{β} u (x) |

where $β$ ranges over all multi-indices of appropriate orders. For functions with kth order derivatives which are Holder continuous with exponent $α$ , the appropriate semi-norm is given by

[u]_{k, α; Ω} = \sup_{\overset{x, y \in Ω}{| β | = k}} \frac{| D^{β} u (x) - D^{β} u (y) |}{| x - y |^{α}}

which gives a full norm of

| u |_{k, α; Ω} = | u |_{k; Ω} + [u]_{k, α; Ω} = \sum_{| β | \leq k} \sup_{x \in Ω} | D^{β} u (x) | + \sup_{\overset{x, y \in Ω}{| β | = k}} \frac{| D^{β} u (x) - D^{β} u (y) |}{| x - y |^{α}} .

For the interior estimates, the norms are weighted by the distance to the boundary

d_{x} = d (x, \partial Ω)

raised to the same power as the derivative, and the seminorms are weighted by

d_{x, y} = \min (d_{x}, d_{y})

raised to the appropriate power. The resulting weighted interior norm for a function is given by

| u |_{k, α; Ω}^{*} = | u |_{k; Ω}^{*} + [u]_{k, α; Ω}^{*} = \sum_{| β | \leq k} \sup_{x \in Ω} | d_{x}^{| β |} D^{β} u (x) | + \sup_{\overset{x, y \in Ω}{| β | = k}} d_{x, y}^{k + α} \frac{| D^{β} u (x) - D^{β} u (y) |}{| x - y |^{α}}

It is occasionally necessary to add "extra" powers of the weight, denoted by

| u |_{k, α; Ω}^{(m)} = | u |_{k; Ω}^{(m)} + [u]_{k, α; Ω}^{(m)} = \sum_{| β | \leq k} \sup_{x \in Ω} | d_{x}^{| β | + m} D^{β} u (x) | + \sup_{\overset{x, y \in Ω}{| β | = k}} d_{x, y}^{m + k + α} \frac{| D^{β} u (x) - D^{β} u (y) |}{| x - y |^{α}} .

Formulation

The formulations in this section are taken from the text of Template:Harvs.

Interior estimates

Consider a bounded solution $u \in C^{2, α} (Ω)$ on the domain $Ω$ to the elliptic, second order partial differential equation

\sum_{i, j} a_{i, j} (x) D_{i} D_{j} u (x) + \sum_{i} b_{i} (x) D_{i} u (x) + c (x) u (x) = f (x)

where the source term satisfies $f \in C^{α} (Ω)$ . If there exists a constant $λ > 0$ such that the $a_{i, j}$ are strictly elliptic,

\sum a_{i, j} (x) ξ_{i} ξ_{j} \geq λ | ξ |^{2}

for all

x \in Ω, ξ \in ℝ^{n}

and the relevant norms coefficients are all bounded by another constant $Λ$

| a_{i, j} |_{0, α; Ω}, | b_{i} |_{0, α; Ω}^{(1)}, | c |_{0, α; Ω}^{(2)} \leq Λ .

Then the weighted $C^{2, α}$ norm of u is controlled by the supremum of u and the Holder norm of f:

| u |_{2, α; Ω}^{*} \leq C (n, α, λ, Λ) (| u |_{0, Ω} + | f |_{0, α; Ω}^{(2)}) .

Boundary estimates

Let $Ω$ be a $C^{2, α}$ domain (that is to say, about any point on the boundary of the domain the boundary surface can be realized, after an appropriate rotation of coordinates, as a $C^{2, α}$ function), with Dirichlet boundary data that coincides with a function $ϕ (x)$ which is also at least $C^{2, α}$ . Then subject to analogous conditions on the coefficients as in the case of the interior estimate, the unweighted Holder norm of u is controlled by the unweighted norms of the source term, the boundary data, and the supremum norm of u:

| u |_{2, α; Ω} \leq C (n, α, λ, Λ, Ω) (| u |_{0, Ω} + | f |_{0, α; Ω} + | ϕ |_{2, α; \partial Ω}) .

When the solution u satisfies the maximum principle, the first term on the right hand side can be dropped.

Sources

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Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 Template:MathSciNet
Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010

Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 Template:MathSciNet

@@ Line 1: / Line 1: @@
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+In [[mathematics]], the '''Schauder estimates''' are a collection of results due to {{harvs|txt|first=Juliusz|last= Schauder|year=1934|year2=1937|author-link=Juliusz Schauder}} concerning the regularity of solutions to linear, uniformly [[Elliptic operator|elliptic]] [[partial differential equation]]s. The estimates say that when the equation has appropriately [[differentiable|smooth]] terms and appropriately smooth solutions, then the [[Hölder condition|Hölder norm]] of the solution can be controlled in terms of the Hölder norms for the coefficient and source terms. Since these estimates do not assume the existence of the solution, they are called [[a priori estimate]]s.
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+There is both an ''interior'' result, giving a Hölder condition for the solution in interior domains away from the boundary, and a ''boundary'' result, giving the Hölder condition for the solution in the entire domain. The former bound depends only on the spatial dimension, the equation, and the distance to the boundary; the latter depends on the smoothness of the boundary as well.
+The Schauder estimates are a necessary precondition to using the [[method of continuity]] to proving the existence and regularity of solutions to the [[Dirichlet problem]] for elliptic PDEs. This result says that when the coefficients of the equation and the nature of the boundary conditions are sufficiently smooth, there is a smooth classical solution to the PDE.
+== Notation ==
+The Schauder estimates are given in terms of weighted Hölder norms; the notation will follow that given in the text of {{harvs|txt|first=D.|last=Gilbarg|last2=Trudinger|first2=Neil|authorlink2=Neil Trudinger|year=1983}}.
+The supremum norm of a continuous function <math>f \in C(\Omega)</math> is given by
+:<math>|f|_{0;\Omega} = \sup_{x\in\Omega} |f(x)|</math>
+For a function which is Hölder continuous with exponent <math>\alpha</math>, that is to say, <math>f \in C^\alpha (\Omega)</math> the usual [[Hölder condition|Hölder seminorm]] is given by
+:<math>[f]_{0,\alpha;\Omega} = \sup_{x,y\in \Omega} \frac{|f(x)-f(y)|}{|x-y|^\alpha}.</math>
+The sum of the two is the full Hölder norm of ''f''
+:<math>|f|_{0,\alpha;\Omega} = |f|_{0;\Omega} + [f]_{0,\alpha;\Omega} = \sup_{x\in\Omega} |f(x)| + \sup_{x,y\in \Omega} \frac{|f(x)-f(y)|}{|x-y|^\alpha}.</math>
+For differentiable functions ''u'', it is necessary to consider the higher order norms, involving derivatives. The norm in the space of functions with ''k'' continuous derivatives, <math>C^k(\Omega)</math>, is given by
+:<math>|u|_{k;\Omega} = \sum_{|\beta| \leq k} \sup_{x\in \Omega} |D^\beta u(x)|</math>
+where <math>\beta</math> ranges over all [[multi-index notation|multi-indices]] of appropriate orders. For functions with ''k''th order derivatives which are Holder continuous with exponent <math>\alpha</math>, the appropriate semi-norm is given by
+:<math>[u]_{k,\alpha;\Omega} = \sup_{\stackrel{x,y\in \Omega}{|\beta| = k}} \frac{|D^\beta u(x) - D^\beta u(y)|}{|x-y|^\alpha}</math>
+which gives a full norm of
+:<math>|u|_{k,\alpha;\Omega} = |u|_{k;\Omega} + [u]_{k,\alpha;\Omega} = \sum_{|\beta| \leq k} \sup_{x\in \Omega} |D^\beta u(x)| +  \sup_{\stackrel{x,y\in \Omega}{|\beta| = k}} \frac{|D^\beta u(x) - D^\beta u(y)|}{|x-y|^\alpha}.</math>
+For the interior estimates, the norms are weighted by the distance to the boundary
+:<math>d_x = d(x, \partial \Omega)</math>
+raised to the same power as the derivative, and the seminorms are weighted by
+:<math>d_{x,y} = \min (d_x,d_y) </math>
+raised to the appropriate power. The resulting weighted interior norm for a function is given by
+:<math>|u|^*_{k,\alpha;\Omega} = |u|^*_{k;\Omega} + [u]^*_{k,\alpha;\Omega} = \sum_{|\beta| \leq k} \sup_{x\in \Omega} |d_x^{|\beta|} D^\beta u(x)| +  \sup_{\stackrel{x,y\in \Omega}{|\beta| = k}} d_{x,y}^{k+\alpha} \frac{|D^\beta u(x) - D^\beta u(y)|}{|x-y|^\alpha}</math>
+It is occasionally necessary to add "extra" powers of the weight, denoted by
+:<math>|u|^{(m)}_{k,\alpha;\Omega} = |u|^{(m)}_{k;\Omega} + [u]^{(m)}_{k,\alpha;\Omega} = \sum_{|\beta| \leq k} \sup_{x\in \Omega} |d_x^{|\beta|+m} D^\beta u(x)| +  \sup_{\stackrel{x,y\in \Omega}{|\beta| = k}} d_{x,y}^{m+k+\alpha} \frac{|D^\beta u(x) - D^\beta u(y)|}{|x-y|^\alpha}.</math>
+==Formulation==
+The formulations in this section are taken from the text of {{harvs|txt|first=D.|last=Gilbarg|last2=Trudinger|first2=Neil|authorlink2=Neil Trudinger|year=1983}}.
+===Interior estimates===
+Consider a bounded solution <math>u \in C^{2,\alpha}(\Omega)</math> on the domain <math>\Omega</math> to the elliptic, second order partial differential equation
+:<math>\sum_{i,j} a_{i,j}(x) D_i D_j u(x) + \sum_i b_i(x) D_i u(x) + c(x) u(x) = f(x)</math>
+where the source term satisfies <math>f\in C^\alpha(\Omega)</math>. If there exists a constant <math>\lambda > 0</math> such that the <math>a_{i,j}</math> are strictly elliptic,
+:<math>\sum a_{i,j}(x) \xi_i \xi_j \geq \lambda |\xi|^2</math> for all <math>x\in \Omega, \xi \in \mathbb{R}^n</math>
+and the relevant norms coefficients are all bounded by another constant <math>\Lambda</math>
+:<math>|a_{i,j}|_{0,\alpha;\Omega}, |b_i|^{(1)}_{0,\alpha;\Omega}, |c|^{(2)}_{0,\alpha;\Omega} \leq \Lambda.</math>
+Then the weighted <math>C^{2,\alpha}</math> norm of ''u'' is controlled by the supremum of ''u'' and the Holder norm of ''f'':
+:<math>|u|^*_{2,\alpha;\Omega} \leq C(n,\alpha,\lambda,\Lambda) (|u|_{0,\Omega} + |f|^{(2)}_{0,\alpha;\Omega}).</math>
+===Boundary estimates===
+Let <math>\Omega</math> be a <math>C^{2,\alpha}</math> domain (that is to say, about any point on the boundary of the domain the boundary surface can be realized, after an appropriate rotation of coordinates, as a <math>C^{2,\alpha}</math> function), with Dirichlet boundary data that coincides with a function <math>\phi(x)</math> which is also at least <math>C^{2,\alpha}</math>. Then subject to analogous conditions on the coefficients as in the case of the interior estimate, the unweighted Holder norm of ''u'' is controlled by the unweighted norms of the source term, the boundary data, and the supremum norm of ''u'':
+:<math>|u|_{2,\alpha;\Omega} \leq C(n,\alpha,\lambda,\Lambda,\Omega) (|u|_{0,\Omega} + |f|_{0,\alpha;\Omega} + |\phi|_{2,\alpha;\partial\Omega}).</math>
+When the solution ''u'' satisfies the [[maximum principle]], the first term on the right hand side can be dropped.
+==Sources==
+* {{citation|first1=D.|last=Gilbarg|first2=Neil|last2=Trudinger|authorlink2=Neil Trudinger|title=Elliptic Partial Differential Equations of Second Order|publisher=Springer|publication-place=New York|year=1983|isbn=3-540-41160-7}}
+* {{Citation
+|last = Schauder
+|first = Juliusz
+|author-link = Juliusz Schauder
+|year= 1934
+|url=http://www.springerlink.com/content/l5151uv221520628/
+ | title = Über lineare elliptische Differentialgleichungen zweiter Ordnung
+ | periodical = Mathematische Zeitschrift
+ | series =
+ | publication-place = Berlin, Germany
+ | publisher = Springer-Verlag
+ | language = German
+ | volume = 38
+ | issue = 1
+ | pages = 257–282
+|doi = 10.1007/BF01170635
+}} {{MathSciNet|id=1545448}}
+* {{Citation
+|last = Schauder
+|first = Juliusz
+|author-link = Juliusz Schauder
+|year= 1937
+ | title = Numerische Abschätzungen in elliptischen linearen Differentialgleichungen
+ | periodical = Studia Mathematica
+ | series =
+ | publication-place = Lwów, Poland
+ | publisher = Polska Akademia Nauk. Instytut Matematyczny
+ | language = German
+ | volume = 5
+ | issue =
+ | pages = 34–42
+ | url = http://matwbn.icm.edu.pl/ksiazki/sm/sm5/sm516.pdf
+}}
+==Further reading==
+* {{Citation
+ | last1=Courant
+ | first1=Richard
+ | author1-link=Richard Courant
+ | last2=Hilbert
+ | first2=David
+ | author2-link=David Hilbert
+ | title=Methods of Mathematical Physics
+ | volume=2
+ | edition=1st English
+ | publisher=Wiley-Interscience
+ | date=1989
+ | place=New York
+ | isbn=0-471-50439-4
+}}
+* {{citation|first1=Qing|last1=Han|first2=Fanghua|last2=Lin|authorlink2=Lin Fanghua|title=Elliptic Partial Differential Equations|publisher=[[Courant Institute of Mathematical Sciences]]|publication-place=New York|year=1997|isbn=0-9658703-0-8|oclc=38168365}} {{MathSciNet|id=1669352}}
+{{DEFAULTSORT:Schauder Estimates}}
+[[Category:Elliptic partial differential equations]]

Lectionary 184: Difference between revisions

Revision as of 18:42, 27 July 2013

Contents

Notation

Formulation

Interior estimates

Boundary estimates

Sources

Further reading

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Lectionary 184: Difference between revisions

Revision as of 18:42, 27 July 2013

Notation

Formulation

Interior estimates

Boundary estimates

Sources

Further reading

Navigation menu

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