--%>

Define Grandfather paradox

Grandfather paradox: The paradox proposed to discount time travel and exhibit why it violates causality. State that your grand-father makes a time machine. In the current time, you employ his time machine to go back in time a few decades to a point before he married his wife (that is your grandmother). You meet up him to talk about things, and an argument results (presumably he does not believe that you are his grandson/granddaughter), and you by accident kill him.

When he died before he met your grandmother and never had children, then your parents could surely never met (one of them did not exist!) and could never have given birth to you. In adding up, when he didn't live to make his time machine, what are you doing here in the precedent alive and with a time machine, when you were never born and it was not at all built?

   Related Questions in Physics

  • Q : What is balmer series Balmer series (J.

    Balmer series (J. Balmer; 1885): An equation that explains the emission spectrum of hydrogen whenever an electron is jumping to the next orbital; four of the lines are in visible spectrum, and the remainder (residue) are in the ultraviolet.

  • Q : Define Kilogram or SI unit of mass

    Kilogram: kg: The basic SI unit of mass that is the only SI unit still maintained by a physical artifact: a platinum-iridium bar reserved in the International Bureau of Weights and Measures at Sevres, France.

  • Q : Define Joule or SI unit of energy Joule

    Joule: J (after J.P. Joule, 1818-1889): The derived SI unit of energy stated as the quantity of work done by moving an object via a distance of 1 m by exerting a force of 1 N; it therefore has units of N m.

  • Q : Describe Solar water heating Solar

    Solar water heating: Solar water heaters are simple, reliable, famous and widespread. They are probably the Low Carbon technology closest to being commercially practised. The most efficient designs concentrate solar radiation onto a small diameter tub

  • Q : Define Heat pumps Heat pumps move heat

    Heat pumps move heat from one place to another. They work similar to refrigeration. The movement of heat takes energy, either electrical energy as in the use of  vapor compression heat pumps or thermal energy as in the use of absorption heat pump

  • Q : Problem on Orbit cycle Calculate the

    Calculate the hot and cold temperature after 25 orbits. Assume a 100kg spherical spacecraft made of aluminum. Assume that the spacecraft is in an equatorial orbit. How is calculation 1 different for a spacecraft in a 90 degree (polar) orbit?

  • Q : Define Schwarzschild radius

    Schwarzschild radius: The radius ‘r’ of the event horizon for a Schwarzschild black hole of mass m is specified by (in geometrized units) r = 2 m. In its conventional units: r = 2 G m/c2

  • Q : Define Centrifugal pseudo force

    Centrifugal pseudo force: A pseudo force which takes place whenever one is moving in uniform circular motion. One feels a "force" directed outward from the center of the motion.

  • Q : Define Planck equation Planck equation:

    Planck equation: The quantum mechanical equation associating to the energy of a photon E to its frequency nu: E = h nu.

  • Q : What is Meissner effect Meissner effect

    Meissner effect (W. Meissner; 1933): The reduction of the magnetic flux in a superconducting metal whenever it is cooled beneath the transition temperature. That is the superconducting materials imitate magnetic fields.