zinating
diff --git a/‎physics/casimir_effect.py‎
Lines changed: 121 additions & 0 deletions b/‎physics/casimir_effect.py‎
Lines changed: 121 additions & 0 deletions
@@ -0,0 +1,121 @@
+"""
+Title : Finding the value of magnitude of either the Casimir force, the surface area
+of one of the plates or distance between the plates provided that the other
+two parameters are given.
+
+Description : In quantum field theory, the Casimir effect is a physical force
+acting on the macroscopic boundaries of a confined space which arises from the
+quantum fluctuations of the field. It is a physical force exerted between separate
+objects, which is due to neither charge, gravity, nor the exchange of particles,
+but instead is due to resonance of all-pervasive energy fields in the intervening
+space between the objects. Since the strength of the force falls off rapidly with
+distance it is only measurable when the distance between the objects is extremely
+small. On a submicron scale, this force becomes so strong that it becomes the
+dominant force between uncharged conductors.
+
+Dutch physicist Hendrik B. G. Casimir first proposed the existence of the force,
+and he formulated an experiment to detect it in 1948 while participating in research
+at Philips Research Labs. The classic form of his experiment used a pair of uncharged
+parallel metal plates in a vacuum, and successfully demonstrated the force to within
+15% of the value he had predicted according to his theory.
+
+The Casimir force F for idealized, perfectly conducting plates of surface area
+A square meter and placed at a distance of a meter apart with vacuum between
+them is expressed as -
+
+F = - ((Reduced Planck Constant ℏ) * c * Pi^2 * A) / (240 * a^4)
+
+Here, the negative sign indicates the force is attractive in nature. For the ease
+of calculation, only the magnitude of the force is considered.
+
+Source :
+- https://en.wikipedia.org/wiki/Casimir_effect
+- https://www.cs.mcgill.ca/~rwest/wikispeedia/wpcd/wp/c/Casimir_effect.htm
+- Casimir, H. B. ; Polder, D. (1948) "The Influence of Retardation on the
+  London-van der Waals Forces", Physical Review, vol. 73, Issue 4, pp. 360-372
+"""
+
+from __future__ import annotations
+
+from math import pi
+
+# Define the Reduced Planck Constant ℏ (H bar), speed of light C, value of
+# Pi and the function
+REDUCED_PLANCK_CONSTANT = 1.054571817e-34  # unit of ℏ : J * s
+
+SPEED_OF_LIGHT = 3e8  # unit of c : m * s^-1
+
+
+def casimir_force(force: float, area: float, distance: float) -> dict[str, float]:
+
+    """
+    Input Parameters
+    ----------------
+    force -> Casimir Force : magnitude in Newtons
+
+    area -> Surface area of each plate : magnitude in square meters
+
+    distance -> Distance between two plates : distance in Meters
+
+    Returns
+    -------
+    result : dict name, value pair of the parameter having Zero as it's value
+
+    Returns the value of one of the parameters specified as 0, provided the values of
+    other parameters are given.
+    >>> casimir_force(force = 0, area = 4, distance = 0.03)
+    {'force': 6.4248189174864216e-21}
+
+    >>> casimir_force(force = 2635e-13, area = 0.0023, distance = 0)
+    {'distance': 1.0323056015031114e-05}
+
+    >>> casimir_force(force = 2737e-21, area = 0, distance = 0.0023746)
+    {'area': 0.06688838837354052}
+
+    >>> casimir_force(force = 3457e-12, area = 0, distance = 0)
+    Traceback (most recent call last):
+        ...
+    ValueError: One and only one argument must be 0
+
+    >>> casimir_force(force = 3457e-12, area = 0, distance = -0.00344)
+    Traceback (most recent call last):
+        ...
+    ValueError: Distance can not be negative
+
+    >>> casimir_force(force = -912e-12, area = 0, distance = 0.09374)
+    Traceback (most recent call last):
+        ...
+    ValueError: Magnitude of force can not be negative
+    """
+
+    if (force, area, distance).count(0) != 1:
+        raise ValueError("One and only one argument must be 0")
+    if force < 0:
+        raise ValueError("Magnitude of force can not be negative")
+    if distance < 0:
+        raise ValueError("Distance can not be negative")
+    if area < 0:
+        raise ValueError("Area can not be negative")
+    if force == 0:
+        force = (REDUCED_PLANCK_CONSTANT * SPEED_OF_LIGHT * pi**2 * area) / (
+            240 * (distance) ** 4
+        )
+        return {"force": force}
+    elif area == 0:
+        area = (240 * force * (distance) ** 4) / (
+            REDUCED_PLANCK_CONSTANT * SPEED_OF_LIGHT * pi**2
+        )
+        return {"area": area}
+    elif distance == 0:
+        distance = (
+            (REDUCED_PLANCK_CONSTANT * SPEED_OF_LIGHT * pi**2 * area) / (240 * force)
+        ) ** (1 / 4)
+        return {"distance": distance}
+    raise ValueError("One and only one argument must be 0")
+
+
+# Run doctest
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()