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:<math>E=K_{0}t+\frac{1}{2}\rho{}vt^2</math>
 
:<math>E=K_{0}t+\frac{1}{2}\rho{}vt^2</math>
;All {{w|kinematics}} equations
+
:All kinematics equations
Most kinematics equations tend to make heavy use of constants, addition, powers, and multiplication. This specific equation resembles the actual kinematics equation d = vt + 1/2at^2, but replaces a (acceleration) with v (velocity) times <math>\rho{}</math> (density) and replaces velocity with "K<sub>0</sub>", which is not a term used in kinematics.
 
  
 
:<math>K_{n}=\sum_{i=0}^{\infty}\sum_{\pi=0}^{\infty}(n-\pi)(i+e^{\pi-\infty})</math>
 
:<math>K_{n}=\sum_{i=0}^{\infty}\sum_{\pi=0}^{\infty}(n-\pi)(i+e^{\pi-\infty})</math>
;All {{w|number theory}} equations
+
:All number theory equations
Randall jokes about how number theory often involves the use of summations. The use of ''&pi;'' as an integer variable in the double summation is a joke, as ''&pi;'' is essentially always used for the well-known constant 3.14159..., not a variable. The use of ''i'' as a summation variable '''is''' common, though it can also be confused with the imaginary unit &radic;-1. The constants ''e'', ''i'', and ''&pi;'', as well as the theoretical upper bound <math>\infty</math>, often appear in number theory equations.
 
  
:<math>\frac{\partial}{\partial{t}}\nabla\!\cdot\!\rho=\frac{8}{23}\int\!\!\!\!\int\!\!\!\!\!\!\!\!\!\subset\!\!\supset\rho\,{ds}\,{dt}\cdot{}\rho\frac{\partial}{\partial\nabla}</math>
+
:<math>\frac{\partial}{\partial{t}}\nabla\cdot\rho=\frac{8}{23}\oint\!\!\!\!\oint\rho\,{ds}\,{dt}\cdot{}\rho\frac{\partial}{\partial\nabla}</math>
;All {{w|fluid dynamics}} equations
+
:All fluid dynamics equations
Fluid dynamics equations often involve copious integrals, especially those over closed contours as done here, which are often the main telling factors of those equations to an outsider. The time derivative and gradient operator <math>\nabla</math> are common in fluid dynamics, mostly via the Navier-Stokes equation, and the fluid density <math>\rho</math> is one of the functions of central importance. The fraction 8/23 is a comically weird choice, but various unexpected fractions do pop up in fluid dynamics. The ds and dt go with the double contour integral (s is probably distance, t is time), but the derivative with respect to <math>\nabla</math> at the end is very much not allowed.
 
  
 
:<math>|\psi_{x,y}\rangle=A(\psi)A(|x\rangle\otimes|y\rangle)</math>
 
:<math>|\psi_{x,y}\rangle=A(\psi)A(|x\rangle\otimes|y\rangle)</math>
;All {{w|quantum mechanics}} equations
+
:All quantum mechanics equations
Quantum mechanics often involves some of the foreign-looking symbols listed, including {{w|Bra–ket notation|bra-ket notation}}, the {{w|Tensor product|tensor product}}, and the Greek letter Psi for a quantum state. Specifically, the left side of the equation is a ket state labeled Psi that depends on x and y (probably positions), while the right-hand side may be an operator A that depends on the state Psi (it is very unusual to have such a dependence) acting on what looks like another copy of that operator which depends on the outer product of states labeled by x and y (again strange). A charitable interpretation could be that the second A is the eigenfunction A of the operator A. Normally this is clearly indicated by giving the operator a “hat” (^ symbol) or making the eigenfunction into a ket eigenstate, but since the equation is intentionally nonsense both A’s are left ambiguous. Also note that the bra-ket math is inconsistent here, as the left side is a ket, but the right side is just two A’s, which are either operators or functions but are definitely not kets.
 
  
 
:<math>CH_4+OH+HEAT\rightarrow{}H_2O+CH_{2}+H_2EAT</math>
 
:<math>CH_4+OH+HEAT\rightarrow{}H_2O+CH_{2}+H_2EAT</math>
;All {{w|chemistry}} equations
+
:All chemistry equations
Chemistry equations use formulas of chemical compounds to describe a chemical reaction. Such equations show the starting chemicals on the left side and the resulting products on the right side, as displayed. Sometimes such an equation might optionally indicate that an {{w|activation energy}} is required, for the reaction to take place in a sensible timeframe, e.g. by heating. A reaction requiring heating is usually indicated by a Greek capital letter Delta (''&Delta;'') or a specified temperature above the reaction arrow, however this comic uses the "+ HEAT" term on the left side instead. The joke is that Randall interprets "HEAT" to be another chemical, possibly the nonsensical helium-monastatide, which reacts with Hydrogen (H) to H<sub>2</sub>EAT, which is nonsensical, as heat is transferred energy here, not added matter. Regardless of this, Randall gets the {{w|stoichiometry}} of this equation correct, with the same number of all types of 'atoms' on each side of the equation.
 
  
 
:<math>SU(2)U(1)\times{}SU(U(2))</math>
 
:<math>SU(2)U(1)\times{}SU(U(2))</math>
;All {{w|quantum gravity}} equations
+
:All quantum gravity equations
Quantum gravity uses mathematical {{w|Group (mathematics)|groups}} denoted by uppercase letters, as shown. {{w|Special unitary group|SU(2)}}, {{w|Unitary group|U(1)}}, and {{w|Unitary group|U(2)}} are all well-studied groups, though 'SU(U(2))' makes no sense.  The lack of relator means this expression isn't an equation.
 
  
:[[File:All gauge theory equations.png]]
+
:S<sub>g</sub>=(-1)/(2&epsilon;&#x0304;) i&eth;(&#x302; &xi;<sub>0</sub> &#x2a22; p<sub>&epsilon;</sub> &rho;<sub>v</sub><sup>abc</sup>&sdot;&eta;<sub>0</sub>)&#x302; f&#x0335;<sub>a</sub><sup>0</sup> &lambda;(<span style="display:inline-block; -ms-transform:rotate(180deg); -webkit-transform:rotate(180deg); transform:rotate(180deg);">&xi;</span>) &psi;(0<sub>a</sub>)
;All {{w|gauge theory}} equations
+
:All gauge theory equations
Gauge theory is a subset of field theory. Most gauge theory equations appear to have many strange-looking constants and variables with odd labels. However, almost none of the symbols used here are found or applicable to gauge theory.
 
  
:<math>H(t)+\Omega+G\!\cdot\!\Lambda...\begin{cases}...>0\mathrm{\ (Hubble\ model)}\\
+
:<math>H(t)+\Omega+G\cdot\nabla...\begin{cases}...>0\textrm{\ (Hubble\ model)}\\
...=0\mathrm{\ (Flat\ sphere\ model)}\\
+
...=0\textrm{\ (Flat\ sphere\ model)}\\
...<0\mathrm{\ (Bright\ dark\ matter\ model)}
+
...<0\textrm{\ (Bright\ dark\ matter\ model)}
 
\end{cases}</math>
 
\end{cases}</math>
;All {{w|cosmology}} equations
+
:All cosmology equations
Cosmology is the science of the development and ultimate fate of the universe. The joke here may be pertaining to the different models accepted in the field of cosmology. H is the {{w|Hubble's law#Time-dependence of Hubble parameter|Hubble parameter}}, &Omega; is the universal {{w|Friedmann equations#Density parameter|density parameter}}, G is the {{w|gravitational constant}}, and &Lambda; is the {{w|cosmological constant}}.
+
 
 +
:&#x0124; - u&#x0327;<sub>0</sub> = 0
 +
:All truly deep physics equations
 +
 
 +
* Most '''kinematics''' equations tend to make heavy use of constants, addition, powers, and multiplication. This specific equation resembles the actual kinematics equation d = vt + 1/2at^2, but replaces a (acceleration) with v (velocity) and replaces velocity with "K<sub>0</sub>", which is not a term used in kinematics.
 +
 
 +
* Randall jokes about how '''number theory''' often involves the use of summations. The use of ''&pi;'' as an integer variable in the double summation is a joke, as ''&pi;'' is essentially always used for the well-known constant 3.14159..., not a variable. The use of ''i'' as a summation variable '''is''' common, though it can also be confused with the imaginary unit &radic;-1. The constants ''e'', ''i'', and ''&pi;'', as well as the theoretical upper bound <math>\infty</math>, often appear in number theory equations.
 +
 
 +
* '''Fluid dynamics equations''' often involve copious integrals, especially those over closed contours as done here, which are often the main telling factors of those equations to an outsider.
 +
 
 +
* '''Quantum mechanics''' often involves some of the foreign-looking symbols listed, including {{w|Bra–ket notation|bra-ket notation}}, the {{w|Tensor product|tensor product}}, and the Greek letter Psi for a quantum state.
 +
 
 +
* '''Chemistry equations''' use formulas of chemical compounds to describe a chemical reaction. Such equations show the starting chemicals on the left side and the resulting products on the right side, as displayed. Sometimes such an equation might optionally indicate that an {{w|activation energy}} is required, for the reaction to take place in a sensible timeframe, e.g. by heating. A reaction requiring heating is usually indicated by a Greek capital letter Delta (''&Delta;'') or a specified temperature above the reaction arrow, however this comic uses the "+ HEAT" term on the left side instead. The joke is that Randall interprets "HEAT" to be another chemical, which reacts with Hydrogen (H) to H<sub>2</sub>EAT, which is non-sensical, as heat is transferred energy here, not added matter. Regardless of this, Randall gets the {{w|stoichiometry}} of this equation correct, with the same number of all types of 'atoms' on each side of the equation.
 +
 
 +
 
 +
* '''Quantum gravity''' uses mathematical {{w|Group (mathematics)|groups}} denoted by uppercase letters, as shown. {{w|Special unitary group|SU(2)}}, {{w|Unitary group|U(1)}}, and {{w|Unitary group|U(2)}} are all well-studied groups, though 'SU(U(2))' makes no sense.  The lack of relator means this expression isn't an equation.  Here is a possible pun, on "Sue you too... you won"... "Sue you, you too", though it's unclear how it fits in here.
 +
 
 +
* '''Gauge theory''' is a subset of field theory. Most gauge theory equations appear to have many strange-looking constants and variables with odd labels.
 +
 
 +
* '''Cosmology''' is the science of the development and ultimate fate of the universe. The joke here may be pertaining to the different models accepted in the field of cosmology. H is the {{w|Hubble's law#Time-dependence of Hubble parameter|Hubble parameter}}, &Omega; is the universal {{w|Friedmann equations#Density parameter|density parameter}}, G is the {{w|gravitational constant}}, and &Lambda; is the {{w|cosmological constant}}.
  
:[[File:All truly deep physics equations.png]]
+
* The joke about the "truly deep physics equations" is that most of the universal physics equations are simple, almost exceedingly so. One example is Einstein's <math>E = mc^2</math>.
;All truly deep {{w|physics}} equations
 
The joke about the "truly deep physics equations" is that most of the universal physics equations are simple, almost exceedingly so. In general, many of these equations are types of [https://en.wikipedia.org/wiki/Conservation_law conservation law] equations, which reflect some of the basic truths of the universe. A hallmark of conservation laws is that the total amount of some physical value does not change, and so one side of the equation is zero, as shown in the example. One example is Einstein's ''E = mc²'', which shows conservation of mass-energy. Noether's theorem shows that conservation laws have a one-to-one correspondence with a symmetry of nature, making these equations truly 'deep'.  
 
  
The title text is referencing the fact that the {{w|magnetic field|electric and magnetic fields}} are often explained to physics students using an analogy with fluid dynamics, as well as the fact that they do share some similarities (only in terms of mathematical description as three-dimensional vector fields) with fluids. The permittivity constant (represented with ''&epsilon;''<sub>0</sub>) and the permeability constant (represented with ''&mu;''<sub>0</sub>) are coefficients that relate the amount of charge required to cause a specific amount of electric flux in a vacuum and the ability of vacuum to support the formation of magnetic fields, respectively. They appear frequently in Maxwell's equations (the equations that define the electric and magnetic fields in classical mechanics), so Randall is making the joke that any surface integral with them in it automatically is an electromagnetism equation.
+
* The title text is referencing the fact that the electric and magnetic fields are often explained to physics students using an analogy with fluid dynamics, as well as the fact that they do share some similarities (only in terms of mathematical description as three-dimensional vector fields) with fluids. The permittivity constant (represented with ''&epsilon;''<sub>0</sub>) and the permeability constant (represented with ''&mu;''<sub>0</sub>) are coefficients that relate the amount of charge required to cause a specific amount of electric flux in a vacuum and the ability of vacuum to support the formation of magnetic fields, respectively. They appear frequently in Maxwell's equations (the equations that define the electric and magnetic fields in classical mechanics), so Randall is making the joke that any surface integral with them in it automatically is an electromagnetism equation.
  
 
==Transcript==
 
==Transcript==
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[[Category:Math]]
 
[[Category:Math]]
 
[[Category:Chemistry]]
 
[[Category:Chemistry]]
[[Category:Cosmology]]
+
[[Category:Astronomy]]

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