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По словам журналистов, Райт типо предоставил цифровые подписи, сделанные с внедрением криптографических ключей, относящихся к первой операции с биткойнами [17] [18]. Гэвин Андресен , которого Райт уговорил приехать на личную встречу в Лондон, также утверждал, что Райт предоставил ему подтверждения и их фальсификация была маловероятной. Но «доказательство», которое Райт предоставил на публике, оказалось липовым, так как то, что он обрисовал в своём блоге, может повторить хоть какой человек, использовав общедоступные данные из блокчейна биткойна [19] [20] [21] [22].
Какие-либо новейшие, но убедительные и просто проверяемые подтверждения, такие как перемещение ранешних цифровых монет, Райт предоставлять отказался наотрез и потом удалил из собственного блога все записи о биткойнах [23]. В году в издании The New Yorker Джошуа Дэвис в собственной статье заявил о том, что ему удалось сузить круг «подозреваемых» до перечня определенных лиц, в который вошли финский экономический социолог доктор Вилли Лехдонвирта и ирландский студент Майкл Клир [24] , позднее закончивший аспирантуру по криптографии в Тринити-колледже в Дублине и в данный момент являющийся аспирантом в Джорджтаунском институте [25].
Клир [26] и Лехдонвирта [27] заявили, что отторгают эти подозрения. Эти трое программистов вместе подавали заявку на патент, в которой использовалось понятие «вычислительно непрактичная реверсия»; это словосочетание находится и в белоснежной книжке Накамото [29]. Доменное имя bitcoin. При личной встрече с Пененбергом все трое заявили, что не имеют дела к Накамото [28]. Позднее в число подозреваемых попал Дейв Клейман, при этом Крейг Райт заявил о связях с ним [30].
В мае года Тед Нельсон представил, что Накамото на самом деле был японский математик Синъити Мотидзуки [31]. Позже в газете The Age была размещена статья, в которой утверждалось, что Мотидзуки отрицает эти догадки, но без ссылки на источник его слов [32]. Издание Vice в году включило в число вероятных кандидатов личности Накамото Гэвина Андресена, Джеда Маккалеба и правительственное агентство [33].
Дастин Д. Траммел, техасский исследователь вопросцев сохранности, подозревался в том, что он является Накамото, но отторг подозрения [34]. В году два израильских математика, Дорит Рон и Ади Шамир , выпустили документ, в котором утверждалось существование связи меж Накамото и Россом Уильямом Ульбрихтом. Они основывали свои подозрения на анализе сети транзакций биткойнов [35]. Позднее они отказались от собственных догадок [36].
Ласло Ханьец, прошлый разраб Bitcoin Core, общавшийся с Накамото по электронной почте, утверждал, что для 1-го человека код разработан «слишком хорошо» [39]. Бэк позднее отторг это предположение [41] [42]. Материал из Википедии — вольной энциклопедии. В Википедии есть статьи о остальных людях с фамилией Накамото. Дата обращения: 5 марта Архивировано 28 декабря года. Дата обращения: 14 декабря His English had the flawless, idiomatic ring of a native speaker.
Who is the real Satoshi Nakamoto? One researcher may have found the answer , TechCrunch. Дата обращения 31 июля Satoshi Nakamoto is probably Nick Szabo 1 декабря The Huffington Post 8 мая Дата обращения: 31 июля Bitcoin: The Future of Money? The Face Behind Bitcoin англ. Newsweek 6 March Дата обращения: 6 марта Slate 26 November Deputies: Newsweek Bitcoin story quoted Satoshi Nakamoto accurately англ. Los Angeles Times 7 March Дата обращения: 9 марта BBC Российская служба.
Дата обращения: 15 сентября Database and Full Node dumps. Insert TSV-files into your database server and run your analysis. Get Full node dumps to speed up your node synchronization. Visualize blockchain data and compare trends across blockchains. Anonymous portfolio tracker. Track the performance of your crypto assets portfolio — completely anonymously. Квитанции по сделкам. Обозреватель сетевых узлов. Learn about node accessibility, locations, consensus and more.
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Help crypto adoption and reduce tax payments. Сопоставить блокчейн. Compare crypto by size, fees, transactions per second, and more. Трекер релизов. Track upcoming hard forks and latest updates to cryptocurrency clients, like Bitcoin Core and Geth. Счётчик уполовинивания.
Digital signatures provide part of the solution, but the main benefits are lost if a trusted party is still required to prevent double-spending. We propose a solution to the double-spending problem using a peer-to-peer network.
The network timestamps transactions by hashing them into an ongoing chain of hash-based proof-of-work, forming a record that cannot be changed without redoing the proof-of-work. The longest chain not only serves as proof of the sequence of events witnessed, but proof that it came from the largest pool of CPU power. As long as honest nodes control the most CPU power on the network, they can generate the longest chain and outpace any attackers.
The network itself requires minimal structure. Overall, our results have demonstrated that system dynamics modeling is a promising approach to investigate the carbon flow mechanisms in emerging industries. At the same time, we acknowledge there exists some limitations to our study and outline future directions for research. First, to reflect the true designed fundamental value of Bitcoin as intended by Nakamoto, our model assumes that the long-term Bitcoin price is primarily influenced by halving mechanism of Bitcoin mining rewards and is subjected to a linear increase every time a reward halving occurs.
While the historical average Bitcoin price between each reward halving occurrence has generally followed this pattern since , it is extremely volatile in real market operation and is subjected to the influence of other factors such as investor expectations. Therefore, a degree of uncertainty remains as to whether the linearity price assumption would hold, particularly as the Bitcoin market continues to grow into the future. Furthermore, our site regulation SR scenario assumes no cost on miners from relocating to clean-energy-based regions.
In reality, there may be certain costs associated with this action, such as transportation. Therefore, although our results suggest that a site regulation SR policy may be more effective that the current punitive carbon tax policy consensus in limiting the total amount of carbon emission of Bitcoin blockchain operations, it is important to note that these are simulations arising from system dynamics modeling and are limited by the assumptions above. Second, the projected carbon emissions of Bitcoin blockchain operation related to electricity production depends on the source which is used for its generation.
In all of except for the Site Regulation SR scenario, we do not consider the potential changes of the Chinese energy sector in the future, which implies that miners would predominantly operate in the coal-based area. While this is certainly true as the current electricity mix in China is heavily dominated by coal, a series of efforts to incentivise electricity production on the basis of renewable energy sources www.
Consequently, these renewable energy-related efforts and policies can potentially affect the electricity consumption and subsequently, the amount of related carbon emission generated from Bitcoin blockchain operation.
Third, it is important to note that although our results suggest that with the broaden usage and application, blockchain technology could become a carbon-intensive technology that hinders the carbon emission reduction efforts around the world, as with any prediction model, many unforeseeable uncertainties could happen in the future that could cause the reality to deviate from the prediction.
While it is true the blockchain technology, and Bitcoin as one of its applications, is, and increasingly will play a significant role in the economy, ultimately, the choice of adopting and using this technology lies in the hands of humans. Consequently, we should carefully evaluate the trade-offs before applying this promising technology to a variety of industries.
This paper constructs a BBCE model to investigate the feedback loops of Bitcoin blockchain and simulates the carbon emission flows of its operations in China. In view of the complexity of Bitcoin blockchain operation and carbon emission process, the BBCE modeling for Bitcoin carbon emission assessment is mainly based on the following assumptions: 1 The electricity consumption of the Bitcoin mining process mainly consists of two types of energy: coal-based energy and hydro-based energy.
Referring to the historical Bitcoin price data, we assume that the long-term Bitcoin price is mainly affected by the halving mechanism of Bitcoin mining rewards. In other words, policies such as market access of Bitcoin miners and carbon tax of the Bitcoin blockchain operations can be rejiggered for different emission intensity levels. By investigating the inner feedback loops and causalities of the systems, BBCE modeling is able to capture the corresponding dynamic behaviors of system variables based on proposed scenarios 33 , Supplementary Fig.
The types, definitions, units, and related references of each variable in Supplementary Fig. The Bitcoin blockchain utilizes Proof-of-Work PoW consensus algorithm for generating new blocks and validating transactions. Bitcoin miners earn a reward if the hash value of target blocks computed by their hardware is validated by all network participants.
On the other hand, transactions packaged in the block are confirmed when the block is formally broadcasted to the Bitcoin blockchain. To increase the probability of mining a new block and getting rewarded, the mining hardware will be updated continuously and invested by network participants for higher hash rate, which would cause the hash rate of the whole network to rise. In order to maintain the constant minute per new block generation process, the difficulty of generating a new block is adjusted based on the current hash rate of the whole Bitcoin network.
The halving mechanism of block reward is designed to control the total Bitcoin circulation maximum of 21 million Bitcoins and prevent inflation. Reward halving occurs every four years, which means that the reward of broadcasting a new block in Bitcoin blockchain will be zero in Overall, the profit of Bitcoin mining can be calculated by subtracting the total cost of energy consumption and carbon emissions from block reward and transaction fees.
Miners will stop investing and updating mining hardware in China when the total cost exceeds the profit rate. Consequently, the whole network hash rate receives a negative feedback due to the investment intensity reductions. The network mining power is determined by two factors: first, the network hash rate hashes computed per second positively accounts for the mining power increase in Bitcoin network when high hash rate miners are invested.
However, the updated Bitcoin miners also attempt to reduce the energy consumption per hash, i. In addition, policy makers may raise the market access standard and create barriers for the low-efficiency miners to participate in Bitcoin mining activities in China. In terms of the energy consumption of the whole network, the power usage effectiveness is introduced to illustrate the energy consumption efficiency of Bitcoin blockchain as suggested by Stoll The site selection strategies directly determine the energy types consumed by miners.
Although the electricity cost of distinctive energies is more or less the same, their carbon emission patterns may vary significantly according to their respective carbon intensity index. In comparison to miners located in hydro-rich regions, miners located in coal-based regions generate more carbon emission flows under the similar mining techniques and energy usage efficiency due to the higher carbon intensity of coal-based energy The proposed BBCE model collects the carbon footprint of Bitcoin miners in both coal-based and hydro-based energy regions to formulate the overall carbon emission flows of the whole Bitcoin blockchain in China.
It also serves as an auxiliary factor to generate the carbon emission per GDP in our model, which provides guidance for policy makers to implement punitive carbon taxation on Bitcoin industry. The time-related Bitcoin blockchain time-series data are obtained from www. In addition, the auxiliary parameters and macroenvironment variables for network carbon emission flows assessment are set and considered through various guidelines.
For example, the carbon intensities of different energies are suggested by Cheng et al. The average energy cost in China and carbon taxation are collected from the World Bank. The site proportion of Bitcoin miners in China are set based on the regional statistics of Bitcoin mining pools in www. Moreover, the monthly historical data of Bitcoin blockchain are utilized for time-related parameter regression and simulation from the period of January to January through Stata software version Based on the regressed parameters, the whole sample timesteps of network carbon emission assessment cover the period from January to January in this study, which is available for scenario investigations under different Bitcoin policies.
The initial value of static parameters in BBCE model are shown in Supplementary Table 2 , the actual values of the parameterizations adopted are reported in Supplementary Methods, and the key quantitative settings of each subsystem are, respectively, run as follows:. It is clear that mining hardware in the Bitcoin network consists of various equipments and their specifications. As a result, the investment intensity in Bitcoin blockchain is computed by the average price of a profitable mining hardware portfolio.
The quantitative relationship between investment intensity and time can be expressed as the following form:. In Eq. Then the Bitcoin miner profits are accumulated by profit rate and investment intensity flows, which can be obtained as follows:. Utilizing the statistics of Bitcoin blockchain, the hash rate of the Bitcoin network is regressed, and the equation is:.
Similarly, the average block size of Bitcoin is consistent with time due to the growing popularity of Bitcoin transactions and investment. The block size is estimated by time and is illustrated as below:. The proportion of Chinese miners in the Bitcoin mining process will gradually decrease if mining Bitcoin in China is not profitable.
So, the proportion parameter in the BBCE model is set as follows:. Suggested by the mining pool statistics obtained from BTC. In addition, the proportion of Chinese Bitcoin miners will gradually decrease if the Bitcoin mining process is no longer profitable in China. The energy consumed per hash will reduce, i. Moreover, the market access standard for efficiency proposed by policy makers also affects network efficiency. Consequently, the mining efficiency can be calculated as follows:.
The above function coefficients of BBCE parameters are regressed and formulated based on the actual Bitcoin blockchain operation data from the period of January to January , and the specific value of each parameter is reported in Supplementary Methods. The mining power of the Bitcoin blockchain can be obtained by network hash rate and mining efficiency.
The equation of mining power is shown as follows:. Finally, the energy consumed by the whole Bitcoin blockchain can be expressed by mining power and power usage effectiveness:. Employing the regional data of Bitcoin mining pools, coal-based and hydro-based energy is proportionally consumed by distinctive Bitcoin pools.
The total carbon flows in Bitcoin blockchain are measured by the sum of both monthly coal-based and hydro-based energy carbon emission growth. The integration of total carbon emission is:. In addition, carbon emissions per GDP are introduced to investigate the overall carbon intensity of the Bitcoin mining process in China, which is formulated by the following equation:.
In addition, the punitive carbon taxation on the Bitcoin blockchain will be conducted by policy makers, i. As a result, the carbon tax of Bitcoin blockchain is set as:. In order to test the suitability and robustness of BBCE modeling system structures and behaviors, three model validation experiments are introduced and conducted in our study, i.
The validation results of the three tests are reported in Supplementary Discussion. Overall, the model validation results indicate that the proposed BBCE model can effectively simulate the causal relationship and feedback loops of carbon emission system in Bitcoin industry, and the parameters in BBCE model have significant consistencies with actual Bitcoin operating time-series data.
In addition, the sensitivity analysis of BBCE model also shows that a slight variation of the BBCE parameters does not lead to the remarkable changes in the model behaviors or the ranking of the intended carbon reduction policies, thus indicating that the proposed BBCE model has excellent behavioral robustness and stability.
Further information on experimental design is available in the Nature Research Reporting Summary linked to this paper. All data are also available from the corresponding authors upon reasonable request. Nakamoto, S. Zheng, Z.
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Calvo-Pardo, Lea Diestelmeier and other anonymous, reviewers for their contributions to the peer review of this work. Peer review reports are available. Reprints and Permissions. Jiang, S. Policy assessments for the carbon emission flows and sustainability of Bitcoin blockchain operation in China. Nat Commun 12, Download citation.
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Переведено на русский по kofitel.ru Перевод: arvicco, grich – kofitel.ru Редакция: Nikolaev, Ivan – kofitel.ru Оригинальная работа Сатоши Накамото по-прежнему рекомендуется к прочтению всем, кто изучает принципы работы Биткойна. Выберите перевод этой работы. Где в блокчейне Биткоина я могу найти оригинальную белую книгу? · kofitel.ru · kofitel.ru · OK.