Confidential Transactions on Bitcoin and the soundness of the currency

Following the announcement about performance improvements in Confidential Transactions in Bitcoin which you can read about here: https://www.reddit.com/r/Bitcoin/comments/7d5zbc/finally_real_privacy_for_bitcoin_transactions/ I’ve been trying to understand the implications for Zcash.

Firstly any improvements to Bitcoin privacy are welcomed but as Pieter Wuille points out:

Bulletproofs and the Pedersen commitments they operate on are perfectly hiding, but not perfectly binding. This roughly means that if they’re adopted inside Bitcoin, and elliptic curve crypto is (completely) broken, new money can be printed. On the flip side, it does mean that the privacy of anyone who used CT in the past is unaffected.

If I am not mistaken this is precisely the same as Zcash (albeit we also have the trusted setup to worry about) with regards to potential unbounded inflation? Is the difference in CT that this would be detectable in some way or is my understanding correct that a coin can be either offer unconditional privacy (as above and in Zcash) or unconditional soundness but never both?

[edit: I guess the cryptographic assumptions are different too i.e the tech here is more well tested and less likely to broken?]

If you could find a technical paper, id take a look, kek posted a similar story but again nothing really detailed, the first thing i gathered was how very much apparently conveyed to the reader it differs from zcash (all negative comparisons, doesnt seem unbiased) maybe those differences make them incomparable, great inquiry, sorry im no real help!

Heres the technical
https://crypto.stanford.edu/bulletproofs/

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haven’t finished reading this, but not the first time somebody’s came-up with privacy tech for BTC. this goes in waves… first schnorr signatures were the thing, then zerocoin, CT, bullet proofs, range proofs, etc… they’ve been doing this for years. bullet proofs might be cool once once we see something on testnet, but, imo, for now, it’s just another paper…

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The most common phrase is “but requires a trusted setup”, hence the PowTau

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Awesome thank you. Some light reading :rofl: Number of typos in that abstract is concerning!

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Reading that research paper and I’m reminded of the saying:

The more you know, the more you know you don’t know.

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