Can you blast through bedrock if you have enough TNT? I was mining and came accross it and I have 45 TNT blocks. If I could blast through it do you get to use the bedrock too?
It's not possible to break bedrock with any amount of TNT, since bedrock has such a high blast resistance that TNT simply can barely make a dent in it, let alone overcome it completely.
Bedrock has a blast resistance of 18,000,000. (That's 3,000 times more durable than obsidian.)
The explosion math is not straightforward, but a great simplification is that a block is destroyed if its blast resistance is overcome by the explosion power applied to it. An explosion's damage is done by radiating a number of lines out from the centre of the blast, and applying damage alone those lines to blocks at intervals (every 0.3 metres) along the lines. If all of a line's damage is absorbed by one or more blocks it has passed through, no farther intervals are checked.
So, the amount of damage a block of TNT can do simultaneously to a particular piece of bedrock is the sum of the damage applied by all the rays that intersect it. This calculation has already been worked on that page as "The minimum block resistance required to absorb maximum blast force of an explosion happening in nearby air". For TNT under optimal conditions (the TNT is sitting on the block), this is 77.67. That means that a block of TNT will destroy a block with 77 points of blast resistance, but not a block with 78.
Explosion damage appears to not be additive (though the deobfuscated code is unclear enough that I'm not 100% certain either way), in that explosion damage seems to be checked for each individual explosion in a separate run of the explosion code and there's no code to save partial blast damage for later explosions to add to, so simultaneous explosions don't add together. We can see this in evidence by causing many, many explosions on a massive scale, and observing that the bedrock appears to remain entirely intact:
As SaintWacko says, the only way to break bedrock is to go into Creative mode. I just wanted to point out that the reason you cannot blast through bedrock with TNT is that bedrock has a blasting point of 18,000,000 damage. Most blocks are in the damage resistance range of 15-30.
Source: Minecraft Wiki
No, actually SevenSidedDie could not be more wrong. It is a common misconception that you can stack damage to a block in minecraft, but in reality it would have to be a single block that does the trick, therefore it would have to be a mod. Does this make sense?
Quote from Wiki "It is a common myth that Bedrock can be destroyed by a sufficient quantity of TNT. Examinations of the Minecraft code have shown that multiple explosions do not add damage to blocks; any block that is not destroyed by one TNT immediately adjacent to it will not be destroyed by additional TNT"
Therefore saying that the TNT damage value would have to be greater than or equal to 18,000,000. Not only does this have to be a TNT block, in the early days of Minecraft Alpha you could tape down your mouse to continually hit the bedrock block, because the damage accumulated to greater than the bedrock value. So if someone were to go into the code and change the damage value of a pick, TNT or whatever it may be to greater than 18,000,000 than it would destroy the Bedrock. So even in theory, it is most definitely impossible...
You cannot blast through bedrock using TNT.
However, you CAN blast through bedrock using a fireball with the explosion power of 1000000, as JL2579 demonstrates in this video:
Notice, I haven't tested this, because, well, every time I did test it, my game crashed.