CAN EARTH BE A BLACK HOLE ?

First let us know what is black hole 

A black-hole is a highly dense thing in space which has a massive gravitation pull that even light can not escape from its gravity.its a distortion in space time curvature where gravity pulls so much that even light can not get out .

As black holes have massive mass it have mssive gravity.To become a black hole it needs two main factor first chandrasekhar limit and the second one is Schwarzschild radius

What is chandrasekhar limit

The Chandrasekhar limit (/tʃʌndrəˈseɪkər/) is the maximum mass of a stable white dwarf star. The currently accepted value of the Chandrasekhar limit is about 1.4 M_☉ (2.765×10³⁰ kg).exceeding chandrasekhar limit a star undegoes formation ofblack hole.by chandrasekhar limit theory our own sun even cant become a black hole.

So to convert  earth a black hole it needs more mass.

What is Schwarzschild radius 

The schwarzschild radius is the radius of the event horizon surrounding a non roatating black hole.

Any object with physical radius smaller than Schwarzschild radius will be a black hole .

at schwarzchild radius the escape velocity is greater than speed of light.

there are two things that affect the escape velocity -the mass of the object and the distance  to the the center of the object,for example a rocket must accelerate to 11.2 km /sec  in order to escape Earth's gravity.if instead that rocket was on a planet with same mass as Earth but half the diameter ,the escape velocity would be 15.8Km/sec .Even though the mass is the same ,the escape velocity is greater ,because the object is smaller r and  more dense..So to attain the radius we have some equation .

The Schwarzchild radius (Rg)of an object of mass(M) is given by the following formula,in which G is the universal gravitational constant and speed of light :

                                                                         Rg =2GM/c2

 Accordingly the sun has a Schwarzchild radius approximately 3 km whereas earths's is only about 9mm 

So if we squished the earths mass into a sphere with a radius of 9mm the escape velocity would be the speed of light .just a wee bit smaller ,and the escape velocity is greater than the speed of light .But the speed of light is the cosmic speed limit,so it would be impossible to escape that tiny sphere ,if you got close enough.

   Any object that is smaller than it's Schwarzschild radius is a black hole-in other words anything with an escape velocity greater than the speed of light is a black hole .

So earth can be black hole if by any virtue we could able to make some modern highly developed machine that can squeeze Big things like The earth into a grain .Which is impossible for now.