there is no science to zombies
there science to space travel
if the dead walked the earth
there bodies would fall apart after a week due to nothing circulating the blood through the body...
they wont be able to walk cause of rigor mortis
here a article..
It's generally accepted by zombie experts that they're going to continue to rot, even as they shamble around the streets. What the movies fail to convey, however, is the gruesome yet strangely hilarious effect the hot sun has on a rotting corpse.
The first concern is
putrefaction. Thanks to the plethora of bacteria we use in our colon for digesting plant matter, called
gut flora, our bodies are ripe for decay the second our heart stops. Since heat speeds the growth of bacteria (which are plenty happy to start feasting on you once your immune system is no longer a concern) the zombie's got a looming expiration date the very second it turns.
Dead bodies bloat because of the gases created by the bacteria, meaning that in warmer areas even Abercrombie Zombies are going to start getting fat in the first few days. After a few weeks of this, the nasty, bloated zombie army is going to start doing something that is simultaneously the most awesome and disturbing thing a zombie can do:
they will start exploding (CAUTION! Pictures!). The warm, moist conditions in the tropical and subtropical parts of the world (or even just summer in the temperate parts) speeds this condition, meaning a July zombie outbreak pretty much anywhere would be over in a few weeks just by virtue of the rampaging monsters bursting like rancid meat balloons.
7 Scientific Reasons a Zombie Outbreak Would Fail (Quickly) | Cracked.com