Factual error: The scientists were surprised that the space suits were able to withstand the intense pressure encountered when they were walking around in the geode 500 miles below the surface of the earth. They should have been - the suits were made of flexible materials. No matter how heat resistant they were they would have to be completely solid (like the white deep-sea suit worn by the bad guy attacking Bond in "For Your Eyes Only") to provide protection from thousands of pounds per square inch of external pressure. The scientists should have been crushed like eggshells the second they stepped off the ship.
Factual error: While Dr. Brazzleton is turning the hydraulic gear, his glasses fragment. If it was hot enough in his helmet to fragment his glasses, then his face should've been burned. (01:44:45)
Factual error: At the beginning of the movie, the space shuttle is landing off course and they only have moments to figure something out. This makes no sense. Shuttles take a long time to land - about an hour from the time of the reentry burn to touchdown. After the burn, reentry begins about a half an hour before touchdown. There is at least 20+ minutes of glide time. Surely somebody would have noticed they were off course a lot sooner than they did.
Continuity mistake: When Dr. Brazzleton is first showing off the laser, we see both wide and close shots. In the close shots, the beams are cylindrical. In the wide shots, the beams spread out. (00:28:40)
Continuity mistake: When the EM tear hits the Golden Gate Bridge, we see a guy looking at the tear and the glass of the car's door is smashed up by the heat. The camera angle changes and we see the glass undamaged. (01:27:05)
Factual error: In the very first shot of the movie David's watch shows an invalid time. If it were 10:30, the hour hand would be between 10 and 11. The hour hand is exactly at the 10:00 mark even though the minute hand is at 30 minutes.
Factual error: When Dr. Keys is giving a lecture, he mentions that sound waves gain wavelength and lose frequency as they enter a denser medium. That's not completely true. Sound does gain wavelength, but frequency NEVER changes. It is velocity and wavelength which change to maintain the relationship velocity = frequency x wavelength. It is impossible for frequency (no. of waves per second) to change since that would mean waves get lost or created from nothing.
Other mistake: When Braz is showing the thing with the mouse in the box, the laser cuts a hole in the concrete, the steel plate and the wall. When the lasers reach the wall, a small plate falls from the wall, revealing another hole with the shape of a bottle. Where does that come from. If he tried the experiment before (explaining the second hole), wouldn't the bottle be vaporized as well? (00:30:05)
Continuity mistake: During the "landing" of the space shuttle, Hilary Swank sets the air brakes to full. The first exterior shot from the back shows the brakes still engaged, the second shot shows them retracted. There was no command to retract them, besides the crew is still trying to slow the shuttle down, so they should still be deployed.
Continuity mistake: When Serge is getting crushed in the last capsule, the same triangular piece of metal from the lower right closes across his face twice. (01:15:45)
Factual error: It is claimed that the Unobtanium shell doesn't conduct heat, but gets stronger from it. If it can't conduct heat, then how do they solder the thermocouple to it and obtain electricity? If the wall could conduct enough heat for the thermocouple then it would have had to have been hot enough to roast the two crew alive.
Factual error: In a few shots through the movie the gauges or screens displaying information, they use "PPI" for pounds per sq. inch instead of PSI. PPI is wrong it's always PSI. The first time you see it is in the scene when they just launch the ship right before they pierce the crust with Braz and Serge for sure.
Plot hole: When they come up with the idea of setting off the 5 bombs separately, there is a computer screen showing a picture of the Earth and the shock waves starting and interfering with each other. Each shock wave starts off from a different point - they are separated by at least 2000 km. But when they are dropping the bombs, they manage to drop them all within 2 hours (judging by the timer that they set on the first bomb). How did they manage to travel 10000 km in 2 hours?
Factual error: If you are in the military, you will note that all of service dresses worn by army and air force officers have their U.S. insignia pinned onto their collars incorrectly. The insignia is supposed to be pinned so that the letters are parallel to the ground, not parallel to the bottom collar. It's a complete myth that movie uniforms are frequently deliberately incorrect to avoid prosecution, so that's not a valid reason.
Factual error: When Eckart is decrypting data from Qualls using primes, the first number he enters is '1', which is not prime. [Some people have debated this, saying that as primes are any numbers not divisible by any number except themselves and 1, 1 must be prime. While it technically fits the description, 1 is generally considered NOT to be prime (http://www.utm.edu/research/primes/lists/small/1000.txt)].