Author: Gamals Ahmed, CoinEx Business Ambassador
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ABSTRACT

Aryacoin is a new cryptocurrency, which allows for decentralized, peer to peer transactions of electronic cash. It is like Bitcoin and Litecoin, but the trading of the coin occurs on sales platforms that have no restriction to use. Further, it was created with the goal of addressing the double spend issues of Bitcoin and does so using a timestamp server to verify transactions. It works by taking the hash of a block of items to be timestamped and widely publishing the hash. The timestamp proves that the data must have existed at the time in order to get the hash. Each timestamp then includes the previous timestamp in its hash, forming a chain.
The Aryacoin team is continuously developing new use cases for the coin, including exchanges where users can exchange the coins without any fees or restrictions, and offline options where the coins can be bought and sold for cash. The coins can also be used on the company’s other platform, mrdigicoin.io. Along with the coin, there is a digital wallet that can be created and controlled by the user entirely, with no control being retained by the Aryacoin team.

1.INTRODUCTION

The concept of Blockchain first came to fame in October 2008, as part of a proposal for Bitcoin, with the aim to create P2P money without banks. Bitcoin introduced a novel solution to the age-old human problem of trust. The underlying blockchain technology allows us to trust the outputs of the system without trusting any actor within it. People and institutions who do not know or trust each other, reside in different countries, are subject to different jurisdictions, and who have no legally binding agreements with each other, can now interact over the Internet without the need for trusted third parties like banks, Internet platforms, or other types of clearing institutions.
When bitcoin was launched it was revolutionary allowing people to transfer money to anytime and anywhere with very low transaction fees . It was decentralized and their is no third party involved in the transaction , only the sender and receiver were involved.
This paper provide a solution to the double-spending problem using a peer-to-peer distributed timestamp server to generate computational proof of the chronological order of transactions.The system is secure as long as honest nodes collectively control more CPU power than any cooperating group of attacker nodes. Bitcoin was made so that it would not be controlled or regulated but now exchanges and governments are regulating bitcoin and other cryptocurrencies at every step. Aryacoin was developed to overcome these restrictions on a free currency.
Aryacoin is a new age cryptocurrency, which withholds the original principle on which the concept of cryptocurrency was established. Combining the best in blockchain technology since the time of its creation, Aryacoin strives to deliver the highest trading and mining standards for its community.

1.1 OVERVIEW ABOUT ARYACOIN

Aryacoin is a new age cryptocurrency, which withholds the original principle on which the concept of cryptocurrency was established. Combining the best in blockchain technology since the time of its creation, Aryacoin strives to deliver the highest trading and mining standards for its community.
Aryacoin is a blockchain based project that allows users to access their wallet on the web and mobile browsers, using their login details.
Aryacoin can be mined; it also can be exchanged by other digital currencies in several world-famous exchanges such as Hitbtc, CoinEx, P2pb2b, WhiteBit, Changelly and is also listed in reputable wallets such as Coinomi and Guarda.
Aryacoin is a coin, which can be used by anyone looking to use cryptocurrency which allows them to keep their privacy even when buying/selling the coin along with while using the coin during transactions. Proof of work and cryptographic hashes allows transactions to verified.
Stable Fee Per AYA is a unique feature of Aryacoin, so by increasing the amount or volume of the transaction, there is no change in the fee within the network, which means that the fee for sending an amount less than 1 AYA is equal to several hundred million AYA. Another unique feature of Aryacoin is the undetectability of transactions in Explorer, such as the DASH and Monero, of course, this operation is unique to Aryacoin.
Using Aryacoin digital currency, like other currencies, international transactions can be done very quickly and there are no limitations in this area as the creators claim.
Aryacoin aims to allow users to access the Aryacoin wallet via the web and mobile browsers using their login details.
Aryacoin is a peer-to-peer electronic cash system that enables users to send and receive payments directly from one party to another, and allow them to transfer funds across borders with no restriction or third party involvement. The blockchain-based system embraces the digital signature, which prevents double spending and low transfer fees, which enables users to transfer huge amounts with very low fees. The proof-of-work consensus mechanism allows each transaction to be verified and confirmed, while anonymity enables users to use the coin anywhere at any time.
According to the website of the operation, each wallet is divided into 2 or more AYA wallet addresses for each transaction, and depending on the volume of the transaction block, the origin, and destination of transactions in the network can not be traced and displayed to the public.
In fact, each wallet in Aryacoin consists of a total of several wallets. The number of these wallets increases per transaction to increase both security and privacy. Aryacoin also uses the dPoW protocol. In the dPoW protocol, a second layer is added to the network to verify transactions, which makes “51% attack” impossible even with more than half of the network hash, and blocks whose Blockchain uses this second layer of security never run the risk of 51% attacks.
AYA has been listed on a number of crypto exchanges, unlike other main cryptocurrencies, it cannot be directly purchased with fiats money. However, You can still easily buy this coin by
first buying Bitcoin from any large exchanges and then transfer to the exchange that offers to trade this coin.

1.1.1 ARYACOIN HISTORY

Aryacoin (AYA) is a new cryptocurrency, which has been created by a group of Iranian developers, is an altcoin which allows for decentralised, peer to peer transactions of electronic cash without any fees whatsoever. Along with the coin, there is a digital wallet that can be created and managed by the user entirely, with no control being retained by the Aryacoin team.
Aryacoin’s founder, Kiumars Parsa, has been a fan of alternative currencies and particularly Bitcoin.
“We see people from all around the world using Blockchain technology and the great benefits that came with it and it then that I decided to solve this puzzle for find a way of bringing the last missing piece to the jigsaw. The idea for Aryacoin was born.” Parsa said.
Parsa and his team of Iranian ex-pats not only persevered but expedited the project and just a year later, in the summer of 2019, the first version of Aryacoin was released. In 2020, Aryacoin is the first and only Iranian coin listed on CMC.
Parsa goes on to state that it is now the strength of the community that has invested in the coin that will ultimately drive its success, alongside its robust technology and appealing 0% network fees.
“We have thousands of voices behind Aryacoin. People for the people make this coin. It is a massive shout out for democracy. This had made us base the whole team strategy on the benefits for both our users and our traders.”
“One key example is that the network fee on AYA Blockchain is 0%. Yes, absolutely nothing, which which differentiates us from other networks. What also differentiates us from other coins is that we have AYAPAY which is the first cryptocurrency Gateway in the world which does not save funds on third party storage with all funds being forwarded directly to any wallet address that the Gateway owner requests”.
“So for the first time ever, and unlike other gateways, incoming funds will be saved on the users account with submitted withdrawal requests then made on the Gateway host website. In AYAPAY which has also been developed by the Aryacoin team, all funds without extra fees or extra costs will directly forwarded to users wallets. We have named this technology as CloudWithdrawal.”
“We are continuously challenging ourselves as it is a crowded marketplace. We are striving to have a safer Blockchain against 51% attacks, faster confirmations speeds of transactions, cheaper network fee, growing the market by cooperation with Top tier Exchangers.”

1.1.2 ARYACOIN’S MAIN GOAL

Aryacoin’s main goal is to educate people and give them the freedom to use cryptocurrency in any way they want. Aryacoin empowers the users to transfer, pay, trade cryptocurrency from any country around the globe.
Platforms that have been created by Aryacoin Team, as well as those that will go live in future, operate on the same principle and exclude absolutely no one.

1.1.3 PROBLEM ARYACOIN SEEKS TO SOLVE

Aryacoin aims to provide a long-term solution to the problem of double spending, which is still common in the crypto market. The developers of the system have created a peer-to-peer distributed timestamp server that generates computational proof of the transactions as they occur.
Besides, the system remains secure provided honest nodes control more CPU power than any cooperating group of attacker nodes. While Bitcoin was designed not to be regulated or controlled, many exchanges and governments have put regulatory measures on the pioneer cryptocurrency at every step. Aryacoin aims to overcome these restrictions as a free digital currency.

1.1.4 BENEFITS OF USING ARYACOIN

Aryacoin solution offers the following benefits:

• Real-time update: whether you’re going on a holiday or a business trip, no problem. You can access your coins all over the world.
• Instant operations: Aryacoin makes it quite easy for you to use your digital wallet and perform various operations with it.
• Safe and secure: all your data is stored encrypted and can only be decrypted with your private key, seed, or password.
• Strong security: The system has no control over your wallet. You are 100% in charge of your wallet and funds.

1.1.5 ARYACOIN FEATURES

1. Anonymity
The coin provides decent level of anonymity for all its users. The users can send their transactions to any of the public nodes to be broadcasted , the transaction sent to the nodes should be signed by the private key of the sender address . This allows the users to use the coin anywhere any time , sending transactions directly to the node allows users from any place and country .
2. Real Life Usage
aryacoin’s team is continuously developing new and innovative ways to use the coins , they are currently developing exchanges where the users can exchange the coins without any fees and any restrictions . They also are currently developing other innovative technologies, which would allow users to spend our coins everywhere and anywhere.
3. Offline Exchanges
They are also working with different offline vendors which would enable them to buy and sell the coins directly to our users on a fixed/variable price this would allow easy buy/sell directly using cash . This would allow the coins to be accessible to users without any restrictions which most of the online exchanges have, also increase the value and number of users along with new ways to spend the coin. This would increase anonymity level of the
coin. In addition, introduce new users into the cryptomarket and technology. Creating a revolution, which educates people about crypto and introduce them to the crypto world, which introduces a completely new group of people into crypto and a move towards a Decentralized future!
4. Transactions
When it comes to transactions, Aryacoin embraces a chain of digital signatures, where each owner simply transfers the coin to the next person by digitally signing a hash of the previous transaction and the public key of the next owner. The recipient can then verify the signatures to confirm the chain of ownership. Importantly, Aryacoin comes with a trusted central authority that checks every transaction for double spending.
5. Business Partner with Simplex
Aryacoin is the first and only Iranian digital currency that managed to obtain a trading license in other countries.
In collaboration with the foundation and financial giant Simplex, a major cryptocurrency company that has large companies such as Binance, P2P, Changelly, etc. Aryacoin has been licensed to enter the world’s major exchanges, as well as the possibility of purchasing AYA through Credit Cards, which will begin in the second half of 2020.
Also, the possibility of purchasing Aryacoin through Visa and MasterCard credit cards will be activated simultaneously inside the Aryacoin site. plus, in less than a year, AYA will be placed next to big names such as CoinCapMarket, Coinomi, P2P, Coinpayments and many other world-class brands today.

1.1.6 WHY CHOOSE ARYACOIN?

If you want to use a cryptocurrency that allows you to keep your privacy online even when buying and selling the coins, the Aryacoin team claims that AYA is the way to go. Aryacoin is putting in the work: with more ways to buy and sell, and fixing the issues that were present in the original Bitcoin, plus pushing the boundaries with innovative solutions in cryptocurrencies. You can get started using Aryacoin (AYA) payments simply by having a CoinPayments account!

1.1.7 ARYANA CENTRALIZED EXCHANGE

Aryana, the first Iranian exchange is a unique platform with the following features:

• The first real international Persian exchange that obtains international licenses and is listed in CoinMarketCap.
• The first Iranian exchange that has been cooperating with a legal and European exchange for 3 years.
• The possibility of trading in Tomans (available currency in Iran) at the user’s desired price and getting rid of the transaction prices imposed by domestic sites inside Iran.
• There is an internal fee payment plan by Iranian domestic banks for depositing and withdrawing Tomans for Aryacoin holders in Aryana Exchange.
• The number that you see on the monitor and in your account will be equal to the number that is transferred to your bank account without a difference of one Rial.
• The last but not least, noting the fact that there is a trading in Tomans possibility in Aryana exchange.

Aryana Exchange is using the most powerful, fastest, and most expensive server in the world, Google Cloud Platform (GCP), which is currently the highest quality server for an Iranian site, so that professional traders do not lag behind the market even for a second.
The feature of Smart Trading Robots is one of the most powerful features for digital currency traders. Digital cryptocurrency traders are well aware of how much they will benefit from smart trading robots. In the Aryana exchange, it is possible to connect exchange user accounts to intelligent trading bots and trade even when they are offline.
The injection of $ 1 million a day in liquidity by the WhiteBite exchange to maintain and support the price of Tether and eliminate the Tether fluctuations with Bitcoin instabilities used by profiteers to become a matter of course.

1.1.8 HOW DOES ARYACOIN WORK?

Aryacoin (AYA) tries to ensure a high level of security and privacy. The team has made sure to eliminate any trading restrictions for the network users: no verification is required to carry out transactions on AYA, making the project truly anonymous, decentralized, and giving it a real use in day-to-day life. The Delayed-Proof-of-Work (dPoW) algorithm makes the Aryacoin blockchain immune to any attempts of a 51% attack. AYA defines a coin as a chain of digital signatures — each owner transfers the coin to the next owner by digitally signing the hash of the previous transaction and the public key of the next owner, and the receiver verifies the signatures and the chain of ownership.

2. ARYACOIN TECHNOLOGY

2.1 PROOF-OF-WORK

They use a proof-of-work system similar to Adam Back’s Hashcash to implement a distributed timestamp server on a peer-to-peer basis, rather than newspaper or Usenet publications. The proof-of-work involves scanning for a value that when hashed, such as with SHA-256, the hash begins with a number of zero bits. The average work required is exponential in the number of zero bits required and can be verified by executing a single hash.
For their timestamp network, they implement the proof-of-work by incrementing a nonce in the block until a value is found that gives the block’s hash the required zero bits. Once the CPU effort has been expended to make it satisfy the proof-of-work, the block cannot be changed without redoing the work. As later blocks are chained after it, the work to change the block would include redoing all the blocks after it.
The proof-of-work also solves the problem of determining representation in majority decision making. If the majority were based on one-IP-address-one-vote, it could be subverted by anyone able to allocate many IPs. Proof-of-work is essentially one-CPU-one-vote. The majority decision is represented by the longest chain, which has the greatest proof-of-work effort invested in it. If honest nodes control a majority of CPU power, the honest chain will grow the fastest and outpace any competing chains. To modify a past
block, an attacker would have to redo the proof-of-work of the block and all blocks after it, then catch up with, and surpass the work of the honest nodes.

2.2 NETWORK

The steps to run the network are as follows:

• New transactions are broadcast to all nodes.
• Each node collects new transactions into a block.
• Each node works on finding a difficult proof-of-work for its block.
• When a node finds a proof-of-work, it broadcasts the block to all nodes.
• Nodes accept the block only if all transactions in it are valid and not already spent.

This is a very simple system that makes the network fast and scalable, while also providing a decent level of anonymity for all users. Users can send their transactions to any of the public nodes to be broadcast, and the private key of the sender’s address should sign any transaction sent to the nodes. This way, all transaction info remains strictly confidential. It also allows users to send transactions directly to the node from any place at any time and allows the transferring of huge amounts with very low fees.

2.3 AYAPAY PAYMENT SERVICES GATEWAY:

According to creators Aryacoin, the development team has succeeded in inventing a new blockchain technology for the first time in the world, which is undoubtedly a big step and great news for all digital currency enthusiasts around the world.
This new technology has been implemented on the Aryacoin AYAPAY platform and was unveiled on October 2. AYAPAY payment platform is the only payment gateway in the world that does not save money in users’ accounts and transfers incoming coins directly to any wallet address requested by the gateway owner without any additional transaction or fee.
In other similar systems or even systems such as PayPal, money is stored in the user account.

2.4 CONSENSUS ALGORITHM IN ARYACOIN

The devs introduced the Delayed-Proof-of-Work (dPoW) algorithm, which represents a hybrid consensus method that allows one blockchain to take advantage of the security provided by the hashing power of another blockchain. The AYA blockchain works on dPoW and can use such consensus methods as Proof-of-Work (PoW) or Proof-of-Stake (PoS) and join to any desired PoW blockchain. The main purpose of this is to allow the blockchain to continue operating without notary nodes on the basis of its original consensus method. In this situation, additional security will no longer be provided through the attached blockchain, but this is not a particularly significant problem. dPoW can improve the security level and reduce energy consumption for any blockchain.

2.5 DOUBLE-SPEND PROBLEM AND SOLUTION

One of the main problems in the blockchain world is that a receiver is unable to verify whether or not one of the senders did not double-spend. Aryacoin provides the solution, and has established a trusted central authority, or mint, that checks every transaction for double-spending. Only the mint can issue a new coin and all the coins issued directly from the mint are trusted and cannot be double-spent. However, such a system cannot therefore
be fully decentralized because it depends on the company running the mint, similar to a bank. Aryacoin implements a scheme where the receiver knows that the previous owners did not sign any earlier transactions. The mint is aware of all transactions including which of them arrived first. The developers used an interesting solution called the Timestamp Server, which works by taking a hash of a block of items to be ‘timestamped’ and publishing the hash. Each timestamp includes the previous timestamp in its hash, forming a chain. To modify a block, an attacker would have to redo the proof-of-work of all previous blocks, then catch up with, and surpass the work of the honest nodes. This is almost impossible, and makes the network processes more secure. The proof-of-work difficulty varies according to circumstances. Such an approach ensures reliability and high throughput.

3. ARYACOIN ROADMAP

April 2019: The launch of Aryacoin; AYA ICO, resulting in over 30BTC collected
December 2019: The launch of AYA Pay
April 2020: The successful Hamedan Hardfork, supported by all AYA exchanges, aimed at integrating the dPoW algorithm, improving the security of the AYA blockchain.
June 2020: Aryana Exchange goes live, opening more trading opportunities globally
July 2020: The enabling of our Coin Exchanger
November 2020: The implementation of Smart Contracts into the Aryacoin Ecosystem
Q1 2021: Alef B goes live (more details coming soon)

4. THE NUCYBER NETWORK COMMUNITY & SOCIAL

Website: https://aryacoin.io/
Explorer: https://explorer.aryacoin.io/
Github: https://github.com/Aryacoin/Aryacoin
Twitter: 1.1k followers https://twitter.com/AryacoinAYA
Reddit: 442 members https://github.com/nucypher
Instagram: 3.8k followers https://www.instagram.com/mrdigicoin/ Telegram: 5.9k subscribers https://t.me/AYA_Global

5. SUMMARY

Aryacoin (AYA) is a new age cryptocurrency that combines the best of the blockchain technology and strives to deliver high trading and mining standards, enabling users to make peer-to-peer decentralized transactions of electronic cash. Aryacoin is part of an ecosystem that includes payment gateway Ayapay and the Ayabank. AYA has a partnership with the Microsoft Azure cloud platform, which provides the ability to develop applications and store data on servers located in distributed data centers. The network fee for the AYA Blockchain is 0%. In Ayapay service, which has been developed by the Aryacoin team, all funds without extra fees or costs are directly forwarded to users’ wallets with technology called CloudWithdrawal. The devs team is introducing new use cases including exchanges where users will exchange AYA without any restrictions. You can buy AYA on an exchange of your choice, create an Aryacoin wallet, and store it in Guarda.

6. REFERENCES

1) https://coincodex.com/crypto/aryacoin/
2) https://www.icosandstos.com/coin/Aryacoin%20AYA/YuXO60UPF3
3) https://www.publish0x.com/iran-and-cryptocurrency/a-brief-introduction-of-aryacoin-first-ever-iranian-cryptocu-xoldlom
4) https://techround.co.uk/cryptocurrency/aryacoin-the-digital-currency-created-by-iranians/
5) https://bitcoinexchangeguide.com/aryacoin/
6) https://blog.coinpayments.net/coin-spotlight/aryacoin
7) https://guarda.com/aryacoin-wallet

Contents

• Introduction
• What is a double-spend?
• Why is Proof of Work necessary?
• How does PoW work?
• Proof of Work vs. Proof of Stake
• Closing thoughts

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Introduction
Proof of Work (commonly abbreviated to PoW) is a mechanism for preventing double-spends. Most major cryptocurrencies use this as their consensus algorithm. That’s just what we call a method for securing the cryptocurrency’s ledger.
Proof of Work was the first consensus algorithm to surface, and, to date, remains the dominant one. It was introduced by Satoshi Nakamoto in the 2008 Bitcoin white paper, but the technology itself was conceived long before then.
Adam Back’s HashCash is an early example of a Proof of Work algorithm in the pre-cryptocurrency days. By requiring senders to perform a small amount of computing before sending an email, receivers could mitigate spam. This computation would cost virtually nothing to a legitimate sender, but quickly add up for someone sending emails en masse.

What is a double-spend?

A double-spend occurs when the same funds are spent more than once. The term is used almost exclusively in the context of digital money — after all, you’d have a hard time spending the same physical cash twice. When you pay for a coffee today, you hand cash over to a cashier who probably locks it in a register. You can’t go to the coffee shop across the road and pay for another coffee with the same bill.
In digital cash schemes, there’s the possibility that you could. You’ve surely duplicated a computer file before — you just copy and paste it. You can email the same file to ten, twenty, fifty people.
Since digital money is just data, you need to prevent people from copying and spending the same units in different places. Otherwise, your currency will collapse in no time.
For a more in-depth look at double-spending, check out Double Spending Explained.

Why is Proof of Work necessary?

If you’ve read our guide to blockchain technology, you’ll know that users broadcast transactions to the network. Those transactions aren’t immediately considered valid, though. That only happens when they get added to the blockchain.
The blockchain is a big database that every user can see, so they can check if funds have been spent before. Picture it like this: you and three friends have a notepad. Anytime one of you wants to make a transfer of whatever units you’re using, you write it down — Alice pays Bob five units, Bob pays Carol two units, etc.
There’s another intricacy here — each time you make a transaction, you refer to the transaction where the funds came from. So, if Bob was paying Carol with two units, the entry would actually look like the following: Bob pays Carol two units from this earlier transaction with Alice.
Now, we have a way to track the units. If Bob tries to make another transaction using the same units he just sent to Carol, everyone will know immediately. The group won’t allow the transaction to be added to the notepad.
Now, this might work well in a small group. Everyone knows each other, so they’ll probably agree on which of the friends should add transactions to the notepad. What if we want a group of 10,000 participants? The notepad idea doesn’t scale well, because nobody wants to trust a stranger to manage it.
This is where Proof of Work comes in. It ensures that users aren’t spending money that they don’t have the right to spend. By using a combination of game theory and cryptography, a PoW algorithm enables anyone to update the blockchain according to the rules of the system.

How does PoW work?

Our notepad above is the blockchain. But we don’t add transactions one by one — instead, we lump them into blocks. We announce the transactions to the network, then users creating a block will include them in a candidate block. The transactions will only be considered valid once their candidate block becomes a confirmed block, meaning that it has been added to the blockchain.
Appending a block isn’t cheap, however. Proof of Work requires that a miner (the user creating the block) uses up some of their own resources for the privilege. That resource is computing power, which is used to hash the block’s data until a solution to a puzzle is found.
Hashing the block’s data means that you pass it through a hashing function to generate a block hash. The block hash works like a “fingerprint” — it’s an identity for your input data and is unique to each block.
It’s virtually impossible to reverse a block hash to get the input data. Knowing an input, however, it’s trivial for you to confirm that the hash is correct. You just have to submit the input through the function and check if the output is the same.
In Proof of Work, you must provide data whose hash matches certain conditions. But you don’t know how to get there. Your only option is to pass your data through a hash function and to check if it matches the conditions. If it doesn’t, you’ll have to change your data slightly to get a different hash. Changing even one character in your data will result in a totally different result, so there’s no way of predicting what an output might be.
As a result, if you want to create a block, you’re playing a guessing game. You typically take information on all of the transactions that you want to add and some other important data, then hash it all together. But since your dataset won’t change, you need to add a piece of information that is variable. Otherwise, you would always get the same hash as output. This variable data is what we call a nonce. It’s a number that you’ll change with every attempt, so you’re getting a different hash every time. And this is what we call mining.
Summing up, mining is the process of gathering blockchain data and hashing it along with a nonce until you find a particular hash. If you find a hash that satisfies the conditions set out by the protocol, you get the right to broadcast the new block to the network. At this point, the other participants of the network update their blockchains to include the new block.
For major cryptocurrencies today, the conditions are incredibly challenging to satisfy. The higher the hash rate on the network, the more difficult it is to find a valid hash. This is done to ensure that blocks aren’t found too quickly.
As you can imagine, trying to guess massive amounts of hashes can be costly on your computer. You’re wasting computational cycles and electricity. But the protocol will reward you with cryptocurrency if you find a valid hash.
Let’s recap what we know so far:

• It’s expensive for you to mine.
• You’re rewarded if you produce a valid block.
• Knowing an input, a user can easily check its hash — non-mining users can verify that a block is valid without expending much computational power.

So far, so good. But what if you try to cheat? What’s to stop you from putting a bunch of fraudulent transactions into the block and producing a valid hash?
That’s where public-key cryptography comes in. We won’t go into depth in this article, but check out What is Public-Key Cryptography? for a comprehensive look at it. In short, we use some neat cryptographic tricks that allow any user to verify whether someone has a right to move the funds they’re attempting to spend.
When you create a transaction, you sign it. Anyone on the network can compare your signature with your public key, and check whether they match. They’ll also check if you can actually spend your funds and that the sum of your inputs is higher than the sum of your outputs (i.e., that you’re not spending more than you have).
Any block that includes an invalid transaction will be automatically rejected by the network. It’s expensive for you to even attempt to cheat. You’ll waste your own resources without any reward.
Therein lies the beauty of Proof of Work: it makes it expensive to cheat, but profitable to act honestly. Any rational miner will be seeking ROI, so they can be expected to behave in a way that guarantees revenue.

Proof of Work vs. Proof of Stake

There are many consensus algorithms, but one of the most highly-anticipated ones is Proof of Stake (PoS). The concept dates back to 2011, and has been implemented in some smaller protocols. But it has yet to see adoption in any of the big blockchains.
In Proof of Stake systems, miners are replaced with validators. There’s no mining involved and no race to guess hashes. Instead, users are randomly selected — if they’re picked, they must propose (or “forge”) a block. If the block is valid, they’ll receive a reward made up of the fees from the block’s transactions.
Not just any user can be selected, though — the protocol chooses them based on a number of factors. To be eligible, participants must lock up a stake, which is a predetermined amount of the blockchain’s native currency. The stake works like bail: just as defendants put up a large sum of money to disincentivize them from skipping trial, validators lock up a stake to disincentivize cheating. If they act dishonestly, their stake (or a portion of it) will be taken.
Proof of Stake does have some benefits over Proof of Work. The most notable one is the smaller carbon footprint — since there’s no need for high-powered mining farms in PoS, the electricity consumed is only a fraction of that consumed in PoW.
That said, it has nowhere near the track record of PoW. Although it could be perceived as wasteful, mining is the only consensus algorithm that’s proven itself at scale. In just over a decade, it has secured trillions of dollars worth of transactions. To say with certainty whether PoS can rival its security, staking needs to be properly tested in the wild.

Closing thoughts

Proof of Work was the original solution to the double-spend problem and has proven to be reliable and secure. Bitcoin proved that we don’t need centralized entities to prevent the same funds from being spent twice. With clever use of cryptography, hash functions, and game theory, participants in a decentralized environment can agree on the state of a financial database.