Some ERC20 tokens are deployed on different blockchains, but they keep the same prices no matter what, how does it work? for example GMT token got 2 smart contracts, one on solana (first implementation) and the other one on BSC ( recent one) , how come the price remains same while the solana one was deployed at first?
The ERC20 that represents SOL in BSC is basically a stablecoin, not a free floating price like native SOL is. Exactly like wETH is worth the same as ETH or wBTC is worth the same as BTC. wBTC cannot be minted unless you transfer BTC to the vault. Probably SOL in BSC is the consequence of a bridge from Solana network to the Binance Smart Chain.
I hope that helps