Beyond the year 2140

[pawanjain]

So we know that the only reward bitcoin miners will have, after the year 2140 when all the bitcoins are mined from the total bitcoin supply, is the transaction fees from all the transactions in the block.
But what would happen in case the mempool is empty and there are no unconfirmed transactions propagated on the bitcoin network (basically no transactions in the block to be mined) .
I know this occurrence is very rare and there will always be transactions on the bitcoin network but just in case ?

Will the bitcoin miner receive nothing since there are no block rewards and no transaction fees to collect since there are no transactions in the block at first place?

Did some search but couldn't find anything through the forum search and chatGPT's answer seems conflicting too.

[FatFork]

Will the bitcoin miner receive nothing since there are no block rewards and no transaction fees to collect since there are no transactions in the block at first place?

Well, in the scenario you described, when there are no transactions in the block, the miner would not receive any transaction fees. So, you've basically already answered your own question.

[DaveF]

Keep in mind 100 years from now more then likely 1 of 2 scenarios will have happened.
1) Bitcoin is used by so many people on a daily basis the odds of having an empty block would be just about 0
or
2) Something happened and people stopped using BTC so the only people using it are just hobbyists or whatever and they don't care about the fees.

Even now there are a lot of coins that have 0 value that are designed to have 0 value that are actively mined.

-Dave

[o_e_l_e_o]

But what would happen in case the mempool is empty and there are no unconfirmed transactions propagated on the bitcoin network (basically no transactions in the block to be mined) .

Even with no transactions, miners would likely continue to mine for a number of reasons:

1 - They will want to unlock their previous block rewards, which are locked for 100 blocks.

2 - Miners and mining pools hold a significant amount of bitcoin. This is especially true of pools such as Binance pool. It is in their own interests to continue to secure the network so their own holdings don't lose value.

3 - We already have a number of protocols, merged mining, and other things of value which are based on bitcoin blocks being found. See for example the RSK OP_RETURN output in almost every block which is currently found. In the future there will likely be many more such projects, and so miners can gain value from elsewhere by mining bitcoin.

[thecodebear]

This is a strange question. Obviously the answer is if there are no transactions then there is no mining reward. But if there are no transactions then that means Bitcoin use has completely stopped and therefore there would be no miners anyway. Anyway, this isn't a realistic worry, since it would literally mean nobody uses Bitcoin anymore. Bitcoin blocks have already been filled for years, bitcoin blocks not being filled is the opposite of bitcoin's issues.

[BlackHatCoiner]

The problem you're mentioning, if existent, will appear much sooner than in 106 years. In less than 25 years, 12th halving will cut block subsidy to less than 0.05 BTC. To give you a picture, currently the average bitcoin earned in fees per block is about 5 times that.

Besides reward unlocking, large entities' holding bitcoin investments and side-networks that work on top of bitcoin (as told above), the assumption that there will be lots of transactions, while sounding desperate, is a reasonable one to make. If there will not be transactions (or lots of them), there will not be much incentive to have bitcoin, let alone to secure it. Security, as far as I understand, will be inevitable to have, as long as there's enough demand to have the network.