Question About Bitcoin Blocks

[theunsgk]

Hi, so I have been doing some research about crypto and I think I am starting to get it XD I only have one main question now:
What will happen if there are no more bitcoin transactions for some reason? Will mining even be possible then?
As I  understand bitcoin mining is essentially verifying transactions, so thats why Im wondering what will happen if there are no transactions to verify.

Thx in advance

(Edit: missed a word :/)

[NeuroticFish]

Hi, so I have been doing some research about crypto and I think I am starting to get it XD I only have one main question now:
What will happen if there are no more bitcoin transactions for some reason? Will mining even be possible then?
As I  understand bitcoin mining is essentially verifying transactions, so thats why Im wondering what will happen if there are no transactions to verify.

Thx in advance

(Edit: missed a word :/)

Mining goes on and creates more blocks every ~10 minutes whether there are transactions to process or not.
How you think it was in the early days of Bitcoin? Just look at the blockchain and you'll see how many empty blocks were mined. And even today, empty blocks are not that rare.

[theunsgk]

Ohh, so if there are transactions they just get verified, but if there are none, empty ones are generated. I assume that if there are transactions to verify mining goes faster, because  you dont have to wait 10 min for a new block?

[witcher_sense]

Hi, so I have been doing some research about crypto and I think I am starting to get it XD I only have one main question now:
What will happen if there are no more bitcoin transactions for some reason? Will mining even be possible then?
As I  understand bitcoin mining is essentially verifying transactions, so thats why Im wondering what will happen if there are no transactions to verify.

Thx in advance

(Edit: missed a word :/)

A very interesting question. Nowadays miners have a clear incentive to mine even an empty block without transactions because they still receive a reward for finding a block. They construct a special transaction called coinbase transaction with which they pay to themselves with block subsidy (currently 6.25 bitcoin) plus transaction fees. If there are no transactions then it means there is no additional reward in the form of transaction fees, but block subsidy still exists. After 2140 there will be no block subsidy anymore, so in the case of the absence of transactions, miners will have no incentive to mine empty blocks. The network will stop for some time or I am missing something.

Ohh, so if there are transactions they just get verified, but if there are none, empty ones are generated. I assume that if there are transactions to verify mining goes faster, because  you dont have to wait 10 min for a new block?

Here is an explanation of how mining works https://www.oreilly.com/library/view/mastering-bitcoin/9781491902639/ch08.html

[theunsgk]

A very interesting question. Nowadays miners have a clear incentive to mine even an empty block without transactions because they still receive a reward for finding a block. They construct a special transaction called coinbase transaction with which they pay to themselves with block subsidy (currently 6.25 bitcoin) plus transaction fees. If there are no transactions then it means there is no additional reward in the form of transaction fees, but block subsidy still exists. After 2140 there will be no block subsidy anymore, so in the case of the absence of transactions, miners will have no incentive to mine empty blocks. The network will stop for some time or I am missing something.

Ohh, so if there are transactions they just get verified, but if there are none, empty ones are generated. I assume that if there are transactions to verify mining goes faster, because  you dont have to wait 10 min for a new block?

Here is an explanation of how mining works https://www.oreilly.com/library/view/mastering-bitcoin/9781491902639/ch08.html

Ok thank you! I am slowly starting  to understand how this works. So like I have it now, after all the bitcoin is mined, mining will be a lot less profitable because no empty blocks will be created, AND you will only be able to take the fee from a transaction as payment, instead of the minting that you can do now with all blocks.

[franky1]

if there are no transactions. then bitcoin is already dead.
if there are transactions then bitcoin is still useful.
once the reward depletes miners are less incentivised to mine PURPOSEFULLY empty blocks just for the reward because there wont be a reward, so they only get paid by adding in transactions.

obviously if there are no users making transactions. and thus no miners wanting to mine for free. the blockchain just halts and stops building on itself.

bitcoin remains useful to users if its affordable to users. it txfee's become stupidly expensive because of limited amount of possible transactions. that will deter usage. and thus shoot miners in the foot.
..
imagine user preference is a max of $2/tx before they move away from using bitcoin.
a block that only holds 2000tx average is only $4k fee total

gentle progression of more transaction count capacity per block ensures that the overall block cost does not have to be met by only 2000 transactions. but progressively 4000tx, 8000 16,000 thus keeping fee's low and keeping bitcoin useful, while combining the fees to award more to miners.. ($8k, $16k, $32k respectively, while individual users still only pay $2 each)

other factors are that there are about 1.5millions asics (distributed within ~20 pools)right now..  where by if transactions become lax we may see many asics drop off EG 1m asics in 13 pools... then 500k asics in 6 pools.
the 'share' of the fee's can be shared between less people meaning each miner gets more of the share
eventually if transactions become so infrequent, it may become only 3 asics running by 3 people who can just about afford to keep mining.
(the difficulty adjusts depending on how many asics are hashing and solving blocks too quick or too slowly)

[theunsgk]

if there are no transactions. then bitcoin is already dead.
if there are transactions then bitcoin is still useful.
once the reward depletes miners are less incentivised to mine PURPOSEFULLY empty blocks just for the reward because there wont be a reward, so they only get paid by adding in transactions.

obviously if there are no users making transactions. and thus no miners wanting to mine for free. the blockchain just halts and stops building on itself.

bitcoin remains useful to users if its affordable to users. it txfee's become stupidly expensive because of limited amount of possible transactions. that will deter usage. and thus shoot miners in the foot.

gentle progression of more transaction count capacity per block ensures that the overall block cost does not have to be met by only 2000 transactions. but progressively 4k, 8k 16k thus keeping fee's low and keeping bitcoin useful, while combining the fees to award more to miners

Ok! What you said makes a lot of sense. Thank you all for your input

[o_e_l_e_o]

I assume that if there are transactions to verify mining goes faster, because  you dont have to wait 10 min for a new block?

No. It makes no difference to the time it takes to mine a block if that block contains zero transactions or 5,000 transactions. The expected average time to the next block is always 10 minutes.

So like I have it now, after all the bitcoin is mined, mining will be a lot less profitable because no empty blocks will be created

Not quite. It's not like after the last halving that mining suddenly becomes less profitable. The block subsidy will half every 210,000 blocks for the next ~120 years. It's a very gradual process by which the block subsidy contributes less and less to the total block reward and the total fees contribute more and more to the total block reward.

An additional incentive for miners to mine empty blocks may come in the form of them wanting to add confirmations to previous transactions or unlock their block rewards from previous blocks, which cannot be spent until they have 100 confirmations.

[theunsgk]

I assume that if there are transactions to verify mining goes faster, because  you dont have to wait 10 min for a new block?

No. It makes no difference to the time it takes to mine a block if that block contains zero transactions or 5,000 transactions. The expected average time to the next block is always 10 minutes.

So like I have it now, after all the bitcoin is mined, mining will be a lot less profitable because no empty blocks will be created

Not quite. It's not like after the last halving that mining suddenly becomes less profitable. The block subsidy will half every 210,000 blocks for the next ~120 years. It's a very gradual process by which the block subsidy contributes less and less to the total block reward and the total fees contribute more and more to the total block reward.

An additional incentive for miners to mine empty blocks may come in the form of them wanting to add confirmations to previous transactions or unlock their block rewards from previous blocks, which cannot be spent until they have 100 confirmations.

Okkk, the block thing I think I understand now. So blocks can contain any amount of transactions, and are made at a certain interval.

The fees will surely be less than the block subsidy gives now though? And the empty blocks wont give any bitcoin, but then just be used to get more confirmations.

If I may, Id like to ask another question: How I understand it, a person gets the "right" to confirm a block if he wins the race to solve the math equation. How does this stop him from corrupting that block? Isnt he still able to potentially change the contents of the block if he wins the race. Does someone check HIM up?

[o_e_l_e_o]

The fees will surely be less than the block subsidy gives now though? And the empty blocks wont give any bitcoin, but then just be used to get more confirmations.

At the moment the block subsidy is 6.25 BTC, and the fees are generally somewhere in the region of 0.1 - 0.2 BTC. Empty blocks can still claim the full 6.25 BTC subsidy, but obviously have no fees to collect.

Somewhere near the start of 2024, the block subsidy will half to 3.125 BTC. 210,000 blocks after that (approximately 4 years), it will half again to 1.5625 BTC. And so on, until it becomes 0 around 2140. Mining an empty block will become unprofitable long before 2140 though. For a period of 40 years before that, the block subsidy will be less than 1000 sats, for instance.

How does this stop him from corrupting that block? Isnt he still able to potentially change the contents of the block if he wins the race. Does someone check HIM up?

The problem they are trying to solve is based on the block itself. There are countless possible solutions for each and every block which is mined. A miner must first construct a block they want to mine (which we call a candidate block), and then solve the necessary problems using that block, and the solution that they find will be unique to their candidate block. Once they find a solution, if they then change the contents of their candidate block the solution will no longer be correct and they would have to start from scratch. The miner then broadcasts their block and the solution to the rest of the network. The rest of the network then examine the block and the solution to verify it all checks out. It someone broadcasts a corrupted or otherwise invalid block, then the rest of the network will simply reject it.

[theunsgk]

The fees will surely be less than the block subsidy gives now though? And the empty blocks wont give any bitcoin, but then just be used to get more confirmations.

At the moment the block subsidy is 6.25 BTC, and the fees are generally somewhere in the region of 0.1 - 0.2 BTC. Empty blocks can still claim the full 6.25 BTC subsidy, but obviously have no fees to collect.

Somewhere near the start of 2024, the block subsidy will half to 3.125 BTC. 210,000 blocks after that (approximately 4 years), it will half again to 1.5625 BTC. And so on, until it becomes 0 around 2140. Mining an empty block will become unprofitable long before 2140 though. For a period of 40 years before that, the block subsidy will be less than 1000 sats, for instance.

How does this stop him from corrupting that block? Isnt he still able to potentially change the contents of the block if he wins the race. Does someone check HIM up?

The problem they are trying to solve is based on the block itself. There are countless possible solutions for each and every block which is mined. A miner must first construct a block they want to mine (which we call a candidate block), and then solve the necessary problems using that block, and the solution that they find will be unique to their candidate block. Once they find a solution, if they then change the contents of their candidate block the solution will no longer be correct and they would have to start from scratch. The miner then broadcasts their block and the solution to the rest of the network. The rest of the network then examine the block and the solution to verify it all checks out. It someone broadcasts a corrupted or otherwise invalid block, then the rest of the network will simply reject it.

Wow! Ok thx for the answer, I appreciate it a lot. Im done asking things for now, so I hope you have a good day/night!

[OgNasty]

Hi, so I have been doing some research about crypto and I think I am starting to get it XD I only have one main question now:
What will happen if there are no more bitcoin transactions for some reason? Will mining even be possible then?
As I  understand bitcoin mining is essentially verifying transactions, so thats why Im wondering what will happen if there are no transactions to verify.

Thx in advance

Think of Bitcoin mining not so much verifying transactions and more like trying to crack a code.  Once the code is cracked, you get a block reward and can add transactions to the blockchain.  You don't HAVE to add transactions to the blockchain, you can just take the block reward and leave the mempool (unprocessed transactions) for the next guy who cracks the code to worry about.

So the amount of transactions included in the block have nothing to do with solving the block "code" and getting the reward.  However, if you want to increase your reward, you will include transactions and receive those transaction fees as well.  No transactions to include?  No sweat.  Lots of transactions to include?  Include whatever you want or nothing at all. 

[Bitcoin_Arena]

Here is an example of an empty block that was mined today earlier today - https://mempool.space/block/000000000000000000057b946ab19b139fbe58a70de0dbfe1fe179281f4568c7 (it only contains one transaction which is the coinbase transaction)

Let's assume nobody made a bitcoin transaction today and the mempool was empty. New empty blocks would still continue to get confirmed in approximately every 10 minutes with miners only earning via block rewards

[franky1]

Think of Bitcoin mining not so much verifying transactions and more like trying to crack a code.  Once the code is cracked, you get a block reward and can add transactions to the blockchain.  

the topic creator was mentioning a scenario of in 2140 when the reward is zero. where the income for miners is very much 100% based on transaction income. where he then asks of a scenario where there are no transactions in mempool to choose from.

[pooya87]

As I  understand bitcoin mining is essentially verifying transactions, so thats why Im wondering what will happen if there are no transactions to verify.

The problem is with your wrong definition. Mining has nothing to do with verifying transactions. A node performs the verification and block construction while the miner only performs the expensive work. That work is essentially computing a lot of hashes (like a brute force attack) to find a result that satisfies the PoW requirement.
Any bitcoin block must have at least one transaction, which is the coinbase transaction that can create the new coins (the block reward). In other words it is optional to include additional transactions.

[witcher_sense]

Okkk, the block thing I think I understand now. So blocks can contain any amount of transactions, and are made at a certain interval.

The number of transactions that can fit into one block is not very easy to calculate because it will depend on many factors that determine the size of each particular transaction (which transaction type P2PKH, P2WPKH, P2SH, P2WSH, or P2TR, how many inputs and outputs it has, etc.). Also, blocks are made at random intervals, but the average interval tends to be close to ten minutes.

And the empty blocks wont give any bitcoin, but then just be used to get more confirmations.

Here is the paradox, if bitcoin lives up to the time when it is no longer profitable to mine empty blocks, there will be no empty blocks because of the mere fact bitcoin survived.

If I may, Id like to ask another question: How I understand it, a person gets the "right" to confirm a block if he wins the race to solve the math equation. How does this stop him from corrupting that block? Isnt he still able to potentially change the contents of the block if he wins the race. Does someone check HIM up?

You have already been answered, but I just want to add that it is the decentralized network (not the miner himself) that decides whether or not a particular miner has a right to add a block to the chain of blocks. If a miner violates the consensus rules by tampering with the block he found, the network will consider him unworthy of the right to add a block and receive a reward for it.

[o_e_l_e_o]

The number of transactions that can fit into one block is not very easy to calculate because it will depend on many factors that determine the size of each particular transaction (which transaction type P2PKH, P2WPKH, P2SH, P2WSH, or P2TR, how many inputs and outputs it has, etc.).

For interest's sake, the highest number of transactions in a single block is 12,239 in block 367,853.

If a miner violates the consensus rules by tampering with the block he found, the network will consider him unworthy of the right to add a block and receive a reward for it.

I understand the point you are making, but I think this is a bad way to word it when considering newbies will be reading it. Saying that a specific miner is "unworthy of the right to add a block" makes it sound like that miner is somehow blacklisted or permanently removed from the network, which is not the case. The block is simply rejected by the first nodes which see it and is not relayed through the rest of the network. Only if an individual miner started spamming invalid blocks in some kind of DDoS attempt would the mining pool it is part of (or other nodes) start to block it.

[franky1]

For interest's sake, the highest number of transactions in a single block is 12,239 in block 367,853.

for factual interests sake it was not 12,239 transactions
it was a heck of alot of 'dead end' data without a payer address and without a receive address

thus not a true example of bitcoins ability to actually TRANSACT (value transfer)

here is one such example of the 'dead end' data
https://www.blockchain.com/btc/tx/3e064b3f2d303c0ff78180ffe76e99a0d9032d406c9ff2df40077b1976c56a57
nothing in -- nothing out

there were only actually 442 transactions (with a utxo paying out to an actual address) in that block

[o_e_l_e_o]

it was a heck of alot of 'dead end' data without a payer address and without a receive address

And yet, a transaction is not defined by the need for a payer address not a receiving address, nor by the amount being transferred nor the fee paid. All the transactions in that block are still valid transactions as per the protocol and were accepted in to a block and accepted by the network. The fact that many of them sent no coins does not change the fact that that block has the highest number of individual transactions within it.

[Husires]

I will quote @theymos ask and @satoshi reply:

Is the fee enough to always ensure the profitability of running a node, even when BitCoin generation stops being profitable?

Right.  Otherwise we couldn't have a finite limit of 21 million coins, because there would always need to be some minimum reward for generating.  In a few decades when the reward gets too small, the transaction fee will become the main compensation for nodes.  I'm sure that in 20 years there will either be very large transaction volume or no volume.

If there are no transactions, the network will die, but then Bitcoin will have a high value and then there will be transactions, or zero transactions and then no one will mine.

We'll worry about this after the last SAT is mined, which we probably won't get.